Attosecond X-ray Pulses Reveal Dancing Electrons Look inside molecules with the world’s most powerful free electron laser

An attosecond is a billionth of a billionth of a second. There are more attoseconds in a second than there are seconds in the current age of the universe.

But it is now possible to produce X-ray pulses whose time scales can be measured in attoseconds. Pulses this short give scientists the ability to take snapshots of subatomic particles in the wild.

Earlier this year, scientists made headlines by using this method to image electrons moving in liquid water. As the technology continues to advance, scientists may be able to use it for watching electrons move in many other kinds of molecules—boosting chemistry, biology, and any other scientific fields that study how molecules behave.

The tool of choice is an X-ray free electron laser (XFEL) such as the recently upgraded Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory in California, which violently undulates electrons to make them emit intense X-ray beams. Pack these beams into short enough pulses, and you have your imaging medium.

Pulses this short give scientists the ability to take snapshots of subatomic particles in the wild.

To use an FEL for electron watching, scientists typically use a technique called the pump-probe method. Scientists first “pump” a target by exciting it with one pulse, then “probe” it with a second pulse that allows scientists to observe the target. If the second pulse arrives within a short enough duration, scientists can watch subatomic particles in their quantum glory with plenty of time to spare before the X-rays can damage the target.

SOURCE: RAHUL RAO


#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/amophysicsawards/
facebook.com/profile.php?id=100092029748922

Enhancing Smart Manufacturing: The Pivotal Role of Spectroscopy in Process Optimization

Rapid technological advancements are significantly transforming conventional manufacturing. Contemporary data science is leading the emergence of ‘smart manufacturing’, inspiring fundamental changes in how processes are developed, monitored, and assessed.1 Smart manufacturing aims to boost productivity, sustainability, and economic performance by seamlessly integrating all operational systems within industrial enterprises.



This article investigates the role of spectroscopy in revolutionizing smart manufacturing, showcasing how it assists in fostering improved product consistency and quality, as well as proactive process optimization.
In-Line Process Analytics

In smart manufacturing, timely and accurate data flow is critical. Manufacturers seek to monitor every step in their process to ensure optimal results. However, significant challenges include preventing defects, gaining precise control over manufacturing parameters, and maintaining adaptability in dynamic environments.

In-line process analytics are crucial to addressing these challenges.2 This approach allows for direct measurement of the main parameters in each process in real-time, which is unique from traditional online analysis methods that use sampling loops. With continuous, real-time data, in-line process analytics enable manufacturers to quickly adjust parameters, optimizing product quality, yield, and throughput.
Spectroscopy: Revolutionizing Manufacturing

Over the past 20 years, industries ranging from pharmaceuticals to polymers and semiconductors have shown an increase in embracing the development of advanced in-line monitoring techniques for process analysis. Spectroscopy stands out in the world of advanced sensing technologies driving in-line process analytics.

Spectroscopy is a method for analyzing the interaction between matter and electromagnetic radiation. It is crucial in smart manufacturing, particularly when optimizing in-line processes for improved overall operational efficiency and product quality.

In combination with machine learning, spectrometers can help predict and prevent defects. By using spectroscopic techniques, manufacturers can gain precise control over processes and ensure optimal product quality and consistency.

The pharmaceutical industry is an example of where the implementation of spectroscopic techniques is becoming essential for quality control. Techniques like Raman spectroscopy make it possible to set up in-line monitoring for therapeutic manufacturing processes, like monoclonal antibodies.3 The measured spectra can subsequently be utilized to identify the concentration and discover other information, such as confirming contaminants or active ingredients.

Other examples include automated process optimization and control.4 For this, a spectrometer detects the chemical signature of the desired product. Variations in reaction conditions, such as pressure or temperature, can reveal the yield of particular product species. Feedback loops can be established as required. Employing optimization algorithms allows the identification of a highly effective combination of reaction parameters for optimal production outcomes.

The data collected is information-rich with spectroscopic techniques regarding concentrations, sample purities, etc., meaning some parameters can be compared for sample-to-sample consistency and quality control.
Avantes’ Spectrometer Solutions

Avantes provides an array of advanced high-speed spectrometers ideal for in-line process optimization, including the next-generation NEXOS5 and VARIUS6 devices. These spectrometers have superior optical performance and customizable characteristics, facilitating high-precision monitoring and control of critical manufacturing parameters with real-time data provision.

The NEXOS Spectrometer is lightweight and compact, integrating various devices and sensors into smart manufacturing systems. Users can choose from multiple configurations of slits and gratings to align with particular requirements, as well as with different communication protocols like USB2, RS232, direct interfacing, and SPI. This flexibility enables manufacturers to adjust quickly based on real-time spectroscopic data and meet various product specifications.

Varius also offers unmatched flexibility, with a novel magnetic connector cover that makes slit replacement easier and enhances performance with a patent-pending improvement to the optical bench. Available in standard compact and industrial (OEM) variations, Varius suits laboratory settings and industrial applications.

Compact spectrometers integrate seamlessly with various sensors and devices in smart manufacturing systems, making them more functional and versatile. The spectrometer can compile comprehensive data from pressure sensors, temperature sensors, flow meters, and other monitoring devices often used in manufacturing for better precision and control. Built for seamless integration into smart manufacturing systems, Avantes’ compact spectrometers provide a customized solution for in-line process optimization.
Case Study: Plasma Etching in the Electronics Industry

To illustrate the practical applications of Avantes’ spectrometer solutions, an electronics industry case study showcases their effectiveness.

Plasma processing is crucial in manufacturing integrated circuits (ICs) and microelectronics. Engineers utilize plasma etching to create intricate features and patterns on semiconductor layers. However, monitoring this process in real-time is critical to ensuring precise control of the material removal, minimizing defects, and optimizing final product quality.

An optical emission spectrometer like Avantes’ AvaSpec-ULS4096CL-EVO (the predecessor of Nexos and Varius) allowed manufacturers to monitor the plasma etching and automated layer deposition processes in real-time.7 The researchers had precise control over material removal from the layers on the ICs, letting them know precisely when all undesired material had been removed (the end point). This resulted in a tightly controlled process that generated high-quality products.

By integrating in-line spectrometers into the study, the researchers significantly improved the plasma processing method's precision and efficiency, enhancing overall quality assurance and manufacturing precision.

Conclusion

In-line spectroscopic tools are crucial in optimizing processes in smart manufacturing operations, enhancing efficiency and product quality while also minimizing waste and defects. Avantes’ compact spectrometers lead this technological revolution, so manufacturers can be confident in navigating modern production’s complexities, equipped with the tools needed for success.

SOURCE: Avantes BV.

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/amophysicsawards/
facebook.com/profile.php?id=100092029748922

Beat the heat with radiative cooling

Tokyo, Japan – Researchers from Japan have been working hard to keep their cool—or at least—keep their nanodevices from overheating. By adding a tiny coating of silicon dioxide to micro-sized silicon structures, they were able to show a significant increase in the rate of heat dissipated. This work may lead to smaller and cheaper electronic devices that can pack in more microcircuits.

As consumer electronics become ever more compact, while still boasting increased processing power, the need to manage waste heat from microcircuits has grown to become a major concern. Some scientific instruments and nanoscale machines require careful consideration of how localized heat will be shunted out of the device in order to prevent damage. Some cooling occurs when heat is radiated away as electromagnetic waves—similar to how the sun’s power reaches the Earth through the vacuum of space. However, the rate of energy transfer can be too slow to protect the performance of sensitive and densely packed integrated electronic circuits. For the next generation of devices to be developed, novel approaches may need to be established to address this issue of heat transmission.

In a study recently published in the journal Physical Review Letters, researchers from Institute of Industrial Science, The University of Tokyo, showed how the rate of radiative heat transfer can be doubled between two micro-scale silicon plates separated by a tiny gap. The key was using a coating of silicon dioxide that created a coupling between the thermal vibrations of the plate at the surface (called phonons) and the photons (which make up the radiation).



“We were able to show both theoretically and experimentally how electromagnetic waves were excited at the interface of the oxide layer that enhanced the rate of heat transfer,” lead author of the study, Saeko Tachikawa says. The small size of the layers compared with the wavelengths of the electromagnetic energy and its attachment to the silicon plate, which carries the energy without loss, allowed the device to surpass the normal limits of heat transfer, and thus cool faster.

Because current microelectronics are already based on silicon, the findings of this research could be easily integrated into future generations of semiconductor devices. “Our work provides insight into possible heat dissipation management strategies in the semiconductor industry, along with various other related fields such as nanotech manufacturing” says senior author, Masahiro Nomura. The research also helps to establish a better fundamental understanding of how heat transfer works at the nanoscale level, since this is still an area of active research.



SOURCE: INSTITUTE OF INDUSTRIAL SCIENCE, THE UNIVERSITY OF TOKYO


#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Quantum entanglement expands to city-sized networks

Three new protocols for generating verifiable quantum entanglement between two nodes in a network have been developed independently by teams in China, Europe and the US. The research, which allows distant quantum memories to exchange quantum information, may constitute a step towards a quantum version of the Internet in which photons travelling down standard optical fibres are used to entangle spatially separated quantum computers.

The delicate nature of quantum information means it does not travel well. A quantum Internet therefore needs devices known as quantum repeaters to swap entanglement between quantum bits, or qubits, at intermediate points. Several researchers have taken steps towards this goal by distributing entanglement between multiple nodes.

In 2020, for example, Xiao-Hui Bao and colleagues in Jian-Wei Pan’s group at the University of Science and Technology of China (USTC) entangled two ensembles of rubidium-87 atoms in vapour cells using photons that had passed down 50 km of commercial optical fibre. Creating a functional quantum repeater is more complex, however: “A lot of these works that talk about distribution over 50, 100 or 200 kilometres are just talking about sending out entangled photons, not about interfacing with a fully quantum network at the other side,” explains Can Knaut, a PhD student at Harvard University and a member of the US team.
Excited atoms

In their latest work, which is published in Nature alongside that of the Harvard team, Bao and colleagues present a more practicable system. At each node, they use a scheme called the Duan-Lukin-Cirac-Zoller (DLCZ) protocol that involves injecting a laser pulse into each of their atomic ensembles. This “write” pulse is composed of many photons, Bao explains, and there is a small chance that it will excite one atom to another state. The excited atom then spontaneously emits a photon, becoming entangled with a collective state of the atomic ensemble in the process. The emitted photons are then sent to a central node, where a measurement is performed that entangles the two ensembles.

The catch is that the DLCZ protocol requires the write pulses at each node to be phase-coherent, which is hard to achieve in spatially separated nodes. In their 2020 work, the USTC researchers did it by sending pulses from the same laser through a beamsplitter, but this would be impractical for real-world networks. In the new work, they stabilized the phases of independent lasers in three locations approximately 12.5 km apart around a central node and demonstrated that they could entangle ensembles at all of them. “By using atomic ensembles it is rather easy to convert from atomic qubits to single photons,” Bao notes.
Diamond memories

The other two teams worked with solid-state quantum memories made from vacancy centres in diamond. The first, headed by Ronald Hanson at QuTech in the Netherlands, stores the state of the qubit in the electronic state of a nitrogen-vacancy centre, as described in a recent arXiv preprint. The second, led by Harvard’s Mikhail Lukin, uses silicon-vacancy centres. These have a much more stable and coherent optical transition than their nitrogen counterparts, but their electronic spins are less stable, losing coherence within about 200 μs.

This short coherence time is problematic because entanglement cannot be used to transfer information unless the entangled states remain coherent long enough for the entanglement to be “heralded” – that is, for information to travel down a classical channel and confirm the success of the entangling operation: “If you cannot store your entanglement longer than a couple of hundred microseconds it’s essentially useless, because at the point when you want to start using it it’s already gone,” Knaut says.

The Harvard team circumvented this problem using something called a photon-nucleus entangling (PHONE) gate, which members of Lukin’s group invented in 2022. “This PHONE gate utilizes the electron spin, but only temporarily as an interface: it immediately transfers the information to the nuclear spin, and the nuclear spin is very long-lived,” Lukin says.

Lukin and colleagues also avoided the need to measure the photons at a central node. Instead, they used a serial entanglement protocol. “When the photon comes to the first node, it gets entangled – you basically do a gate operation between the photon and one of the qubits in the memory,” explains Lukin. “Then the photon comes to another node, you do another logic gate between the photon and the memory, and then eventually you measure a photon. It’s like a distributed quantum computer.”

The flexibility of this scheme enabled them to avoid keeping track of the phase of the photon emitted directly from the vacancy. Instead, they encoded the state of the qubit into two “time bins” – peaks in the electomagnetic field spaced 142 ns apart: “It’s a single photon conceptually but it is a superposition of two time bins,” Knaut says.
Telecom progress


Chris Monroe of Duke University, US, who was not involved in any of the works, finds one aspect of them interesting: “Quantum systems are very discriminating: they work with very specific colours of light, and they don’t typically tend to be telecom [wavelengths],” he says. “Each of these groups has converted the native photon to a telecom photon and that has allowed them to go over a long distance.”

SOURCE: Tim Wogan is a science writer based in the US

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Scientists May Have Found a Particle Made of Pure Force

For more than half a century, particle physicists have theorized the existence of a “glueball,” a particle made entirely of gluons.
While the past few decades have produced some compelling candidates, researchers using the Beijing Electron–Positron Collider II (BEPC-II) in China have discovered another one known as particle X(2370), which contains the same mass as the expected glueball.
If scientists could confirm the existence of a glueball, whether X(2370) or some other particle, it would be a very good sign that the Standard Model of particle physics is on the right track.


The Standard Model is our current best-guess at understanding, well, everything. Often described as a “periodic table of particle physics,” this model describes the nesting doll-like structure of the subatomic world that underpins the universe. Atoms are made of protons and neutrons, which are in turn composed of quarks that are all held together by gluons—the force carrier for the strong nuclear force (one of the four fundamental forces).

While providing an understanding of subatomic physics, the Standard Model also makes predictions as complicated equations can suggest that certain particles should exist even if they’ve never been directly observed. One of these hypothetical particles is the ever-elusive “glueball.” As its name suggests, this “ball” is actually a particle composed entirely of gluons—quarks need not apply. However, finding such a particle requires firing protons and antiprotons at each other at incredible speeds and sorting through the explosive aftermath.

More than 50 years after the glueball’s first theoretical description via quantum chromodynamics (QCD), the theory of the strong nuclear force, scientists have found a few compelling candidates—quite a feat considering we have no real idea what to look for—but haven’t definitively discovered a glueball. Now, a study from scientists working with the Beijing Electron–Positron Collider II (BEPC-II) in China has discovered what’s perhaps the most convincing candidate yet. Scientists found the particle X(2370) by sifting through a decade of data made up of 10 billion samples and finding a candidate with an average mass of 2,395 MeV/c2, the expected mass of a glueball.

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Bullseye! NIST Devises a Method to Accurately Center Quantum Dots Within Photonic Chips

Devices that capture the brilliant light from millions of quantum dots, including chip-scale lasers and optical amplifiers, have made the transition from laboratory experiments to commercial products. But newer types of quantum-dot devices have been slower to come to market because they require extraordinarily accurate alignment between individual dots and the miniature optics that extract and guide the emitted radiation.

Researchers at the National Institute of Standards and Technology (NIST) and their colleagues have now developed standards and calibrations for optical microscopes that allow quantum dots to be aligned with the center of a photonic component to within an error of 10 to 20 nanometers (about one-thousandth the thickness of a sheet of paper). Such alignment is critical for chip-scale devices that employ the radiation emitted by quantum dots to store and transmit quantum information.

For the first time, the NIST researchers achieved this level of accuracy across the entire image from an optical microscope, enabling them to correct the positions of many individual quantum dots. A model developed by the researchers predicts that if microscopes are calibrated using the new standards, then the number of high-performance devices could increase by as much as a hundred-fold.

That new ability could enable quantum information technologies that are slowly emerging from research laboratories to be more reliably studied and efficiently developed into commercial products.

In developing their method, Craig Copeland, Samuel Stavis, and their collaborators, including colleagues from the Joint Quantum Institute (JQI), a research partnership between NIST and the University of Maryland, created standards and calibrations that were traceable to the International System of Units (SI) for optical microscopes used to guide the alignment of quantum dots.

“The seemingly simple idea of finding a quantum dot and placing a photonic component on it turns out to be a tricky measurement problem,” Copeland said.

In a typical measurement, errors begin to accumulate as researchers use an optical microscope to find the location of individual quantum dots, which reside at random locations on the surface of a semiconductor material. If researchers ignore the shrinkage of semiconductor materials at the ultracold temperatures at which quantum dots operate, the errors grow larger. Further complicating matters, these measurement errors are compounded by inaccuracies in the fabrication process that researchers use to make their calibration standards, which also affects the placement of the photonic components.

The NIST method, which the researchers described in an article posted online in Optica Quantum on March 18, identifies and corrects such errors, which were previously overlooked.


#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Significance of quantum dots in nanotechnology | Explained

The story so far: Alexei I. Ekimov, Louis E. Brus, and Moungi G. Bawendi have been awarded the 2023 Nobel Prize for chemistry “for the discovery and synthesis of quantum dots”.

A quantum dot is a really small assembly of atoms (just a few thousand) around a few nanometres wide. The ‘quantum’ in its name comes from the fact that the electrons in these atoms have very little space to move around, so the crystal as a whole displays the quirky effects of quantum mechanics — effects that otherwise would be hard to ‘see’ without more sophisticated instruments. Quantum dots have also been called ‘artificial atoms’ because the dot as a whole behaves like an atom in some circumstances.

SOURCE: By VASUDEVAN MUKUNTH

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

'A dream come true': Nuclear clock breakthrough could revolutionize study of the universe's fundamental forces

By nudging a thorium-229 nucleus into a higher energy state, physicists have made it possible to develop a nuclear clock that could probe the most fundamental forces in physics. However, there is still a long way to go.

Scientists have made a major breakthrough that takes us a step closer to developing a nuclear clock — a device that keeps time based on the inner workings of atoms.

For the first time, physicists have used laser light to bump the nucleus of a thorium atom up to a higher energy level. The discovery paves the way for the development of a new clock whose ticks are not only more precise but can probe the most fundamental forces in the universe.

The researchers published their findings April 29 in the journal Physical Review Letters.
About time

Currently, our most accurate clocks are atomic and keep time by firing lasers at electrons — matching the laser's frequency with the precise jumps across energy levels it causes electrons orbiting atoms to make. This method gives scientists an ultraprecise measurement of the laser's frequency, from which they can extract the "tick" of the atomic clock.

However, atomic clocks are far from perfect. The electrons they rely on to keep time sit outside atoms. They are therefore vulnerable to interference from stray magnetic fields or other environmental effects that can subtly alter their energy levels, the frequency of laser light they subsequently respond to, and therefore the time they keep.

Related: Otherworldly 'time crystal' made inside Google quantum computer could change physics forever

A nuclear clock, on the other hand, would use the energy transitions of nuclei inside the heart of an atom, so they are shielded from outside interference. But many of the gaps between nuclei energy levels are thousands of times greater than those for electrons — meaning they are too large to be crossed with the energy of a laser.

But in the 1970s, scientists found that one isotope, or version, of the element thorium (thorium-229) seemed to have an energy level that could be spanned by laser light.

But finding this precise energy gap has been no simple task. Initially, researchers excited thorium-229 to an energy level far above the two that physicists were actually interested in. They then measured the subtle differences in the energy of light emitted when it fell back down to the higher one compared to the one just below it.

 



The researchers have compared this process to finding the height of a kerb by dropping balls from a skyscraper — the subtle differences in bounce heights when the ball hits the street to when it hits the sidewalk can help them zero in on the small distance between them.

Over the past 50 years, research narrowed the energy required to cause this energy level jump to the tiny fractions of an electron volt — but this precision was still not enough.

"Theory tells us that it was somewhere in the energy range between 0eV and 10 eV, but we need to hit the right frequency with 7 to 8 digit precision to cause an effect," Schumm said. "Scanning the entire search range would take millenia, so we had to narrow down the search range over many years of preparatory experiments."

To finally hone in on the precise value, Schumm and his team trapped around 10 to the power of 17 thorium-229 nuclei (or a million times more nuclei than there are stars in our galaxy) inside crystals of calcium fluoride, which greatly increased the likelihood of finding the desired transition. After many attempts, the researchers directly observed a thorium atom leaping between the energy levels: an energy change of 8.35574 electron volts.

The researchers note that it will take many more years to develop nuclear clocks to the same accuracy of their atomic counterparts. But with this transition finally spotted, the window has finally been opened, and it could enable physicists to probe more deeply into the elusive nature of dark energy, dark matter and the fundamental forces of our universe.

"The nuclear clock will provide an extremely precise measurement of the energy difference between two bound states of the nucleus," Schumm said. "These two binding energies are the result of three out of the four fundamental forces in physics: electromagnetism, the strong nuclear force, and the weak nuclear force. This is in contrast to all atomic clocks, which rely on electromagnetism alone. If one of these three fundamental forces changes as a function of time or location in space, the nuclear clock should see this."

SOURCE: By Ben Turner

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Sound and light waves combine to create advanced optical neural networks

One of the things that sets humans apart from machines is our ability to process the context of a situation and make intelligent decisions based on internal analysis and learned experiences.

Recent years have seen the development of new “smart” and artificially “intelligent” machine systems. While these do have intelligence based on analysing data and predicting outcomes, many intelligent machine networks struggle to contextualize information and tend to just create a general output that may or may not have situational context.

Whether we want to build machines that can make informed contextual decisions like humans can is an ethical debate for another day, but it turns out that neural networks can be equipped with recurrent feedback that allows them to process current inputs based on information from previous inputs. These so-called recurrent neural networks (RNNs) can contextualize, recognise and predict sequences of information (such as time signals and language) and have been used for numerous tasks including language, video and image processing.

There’s now a lot of interest in transferring electronic neural networks into the optical domain, creating optical neural networks that can process large data volumes at high speeds with high energy efficiency. But while there’s been much progress in general optical neural networks, work on recurrent optical neural networks is still limited.
New optoelectronics required

Development of recurrent optical neural networks will require new optoelectronic devices with a short-term memory that’s programmable, computes optical inputs, minimizes noise and is scalable. In a recent study led by Birgit Stiller at the Max Planck Institute for the Science of Light, researchers demonstrated an optoacoustic recurrent operator (OREO) that meets these demands.

The acoustic waves in the OREO link subsequent optical pulses and capture the information within, using it to manipulate the next operations. The OREO is based on stimulated Brillouin-Mandelstam scattering, an interaction between the optical waves and travelling sound waves that’s used to add latency and slow the acoustic velocity. This process enables the OREO to contextualize a time-encoded stream of information using sound waves as a form of memory, which could be used not only to remember previous operations but as a basis to manipulate the output of the current operation – much like in electronic RNNs.

“I am very enthusiastic about the generation of sound waves by light waves and the manipulation of light by the means of acoustic waves,” says Stiller. “The fact that sound waves can create fabrication-less temporary structures that can be seen by light and can manipulate light in a hair-thin optical fibre is fascinating to me. Building a smart neural network based on this interaction of optical and acoustic waves motivated me to embark on this new research direction.”

Designed to function in any optical waveguide, including on-chip devices, the OREO controls the recurrent operation entirely optically. In contrast to previous approaches, it does not need an artificial reservoir that requires complex manufacturing processes. The all-optical control is performed on a pulse-by-pulse basis and offers a high degree of reconfigurability that can be used to implement a recurrent dropout (a technique used to prevent overfitting in neural networks) and perform pattern recognition of up to 27 different optical pulse patterns.

“We demonstrated for the first time that we can create sound waves via light for the purposes of optical neural networks,” Stiller tells Physics World. “It is a proof of concept of a new physical computation architecture based on the interaction and reciprocal creation of optical and acoustic waves in optical fibres. These sound waves are, for example, able to connect several subsequent photonic computation steps with each other, so they give a current calculation access to past knowledge.”
Looking to the future

The researchers conclude that they have, for the first time, combined the field of travelling acoustic waves with artificial neural networks, creating the first optoacoustic recurrent operator that connects information carried by subsequent optical data pulses.

These developments pave the way towards more intelligent optical neural networks that could be used to build a new range of computing architectures. While this research has brought an intelligent context to the optical neural networks, it could be further developed to create fundamental building blocks such as nonlinear activation functions and other optoacoustic operators.

“This demonstration is only the first step into a novel type of physical computation architecture based on combining light with travelling sound waves,” says Stiller. “We are looking into upscaling our proof of concepts, working on other light–sound building blocks and aiming to realise a larger optical processing structure mastered by acoustic waves.”

The research is published in Nature Communications.

#AmoPhysics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

MIT astronomers observe elusive stellar light surrounding ancient quasars

MIT astronomers have observed the elusive starlight surrounding some of the earliest quasars in the universe. The distant signals, which trace back more than 13 billion years to the universe’s infancy, are revealing clues to how the very first black holes and galaxies evolved.

Quasars are the blazing centers of active galaxies, which host an insatiable supermassive black hole at their core. Most galaxies host a central black hole that may occasionally feast on gas and stellar debris, generating a brief burst of light in the form of a glowing ring as material swirls in toward the black hole.

Quasars, by contrast, can consume enormous amounts of matter over much longer stretches of time, generating an extremely bright and long-lasting ring — so bright, in fact, that quasars are among the most luminous objects in the universe.

Because they are so bright, quasars outshine the rest of the galaxy in which they reside. But the MIT team was able for the first time to observe the much fainter light from stars in the host galaxies of three ancient quasars.

Based on this elusive stellar light, the researchers estimated the mass of each host galaxy, compared to the mass of its central supermassive black hole. They found that for these quasars, the central black holes were much more massive relative to their host galaxies, compared to their modern counterparts.

The findings, published today in the Astrophysical Journal, may shed light on how the earliest supermassive black holes became so massive despite having a relatively short amount of cosmic time in which to grow. In particular, those earliest monster black holes may have sprouted from more massive “seeds” than more modern black holes did.

“After the universe came into existence, there were seed black holes that then consumed material and grew in a very short time,” says study author Minghao Yue, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “One of the big questions is to understand how those monster black holes could grow so big, so fast.”

“These black holes are billions of times more massive than the sun, at a time when the universe is still in its infancy,” says study author Anna-Christina Eilers, assistant professor of physics at MIT. “Our results imply that in the early universe, supermassive black holes might have gained their mass before their host galaxies did, and the initial black hole seeds could have been more massive than today.”

Eilers’ and Yue’s co-authors include MIT Kavli Director Robert Simcoe, MIT Hubble Fellow and postdoc Rohan Naidu, and collaborators in Switzerland, Austria, Japan, and at North Carolina State University.

Dazzling cores

A quasar’s extreme luminosity has been obvious since astronomers first discovered the objects in the 1960s. They assumed then that the quasar’s light stemmed from a single, star-like “point source.” Scientists designated the objects “quasars,” as a portmanteau of a “quasi-stellar” object. Since those first observations, scientists have realized that quasars are in fact not stellar in origin but emanate from the accretion of intensely powerful and persistent supermassive black holes sitting at the center of galaxies that also host stars, which are much fainter in comparison to their dazzling cores.

It’s been extremely challenging to separate the light from a quasar’s central black hole from the light of the host galaxy’s stars. The task is a bit like discerning a field of fireflies around a central, massive searchlight. But in recent years, astronomers have had a much better chance of doing so with the launch of NASA’s James Webb Space Telescope (JWST), which has been able to peer farther back in time, and with much higher sensitivity and resolution, than any existing observatory.

In their new study, Yue and Eilers used dedicated time on JWST to observe six known, ancient quasars, intermittently from the fall of 2022 through the following spring. In total, the team collected more than 120 hours of observations of the six distant objects.

“The quasar outshines its host galaxy by orders of magnitude. And previous images were not sharp enough to distinguish what the host galaxy with all its stars looks like,” Yue says. “Now for the first time, we are able to reveal the light from these stars by very carefully modeling JWST’s much sharper images of those quasars.”

A light balance

The team took stock of the imaging data collected by JWST of each of the six distant quasars, which they estimated to be about 13 billion years old. That data included measurements of each quasar’s light in different wavelengths. The researchers fed that data into a model of how much of that light likely comes from a compact “point source,” such as a central black hole’s accretion disk, versus a more diffuse source, such as light from the host galaxy’s surrounding, scattered stars.

Through this modeling, the team teased apart each quasar’s light into two components: light from the central black hole’s luminous disk and light from the host galaxy’s more diffuse stars. The amount of light from both sources is a reflection of their total mass. The researchers estimate that for these quasars, the ratio between the mass of the central black hole and the mass of the host galaxy was about 1:10. This, they realized, was in stark contrast to today’s mass balance of 1:1,000, in which more recently formed black holes are much less massive compared to their host galaxies.

“This tells us something about what grows first: Is it the black hole that grows first, and then the galaxy catches up? Or is the galaxy and its stars that first grow, and they dominate and regulate the black hole’s growth?” Eilers explains. “We see that black holes in the early universe seem to be growing faster than their host galaxies. That is tentative evidence that the initial black hole seeds could have been more massive back then.”

“There must have been some mechanism to make a black hole gain their mass earlier than their host galaxy in those first billion years,” Yue adds. “It’s kind of the first evidence we see for this, which is exciting.”

Source: Jennifer Chu | MIT News
Publication Date:May 6, 2024

#Amo Physics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922

Scifat.com International Research Awards on Atomic, Molecular and Optical Physics

AMO Physics conference organized by ScienceFather group. ScienceFather takes the privilege to invite speakers, participants, students, delegates, and exhibitors from across the globe to its International Conference onAMO Physics conference to be held in the Various Beautiful cites of the world. AMO Physics conference are a discussion of common Inventions-related issues and additionally trade information, share proof, thoughts, and insight into advanced developments in the science inventions service system.

#Amo Physics, #NuclearPhysics,#AtomicNuclei, #NuclearReactions, #Radioactivity, #NuclearFission, #NuclearFusion, #NuclearEnergy, #NuclearPower, #FusionResearch, #FissionReactors, #RadioactiveDecay, #NuclearMedicine, #NuclearAstrophysics, #ParticleAcceleration, #NuclearSafety, #NuclearEngineering, #NuclearWeapons, #RadiationProtection, #NuclearPolicy, #NuclearWasteManagement.

Visit: amo-physics-conferences.scifat.com/

Member Nomation link: https://x-i.me/amocon
Award Nomination link: https://x-i.me/amonom

Get Connected Here
----------------------
----------------------

youtube.com/channel/UCtntbI1RB0O0CFLpr575_fg
instagram.com/ellenqueen777/
facebook.com/profile.php?id=100092029748922