Category Archives: Quantum Physics
What is a quantum particle really like? It’s not what you think – Big Think
Quantum mechanics is known for some very mind-bending claims, like cats being simultaneously dead and alive, and electrons and protons and other denizens of the subatomic world being both particles and waves. Its quite confusing. But, using modern ideas of the quantum world, there are ways to envision exactly what is going on. In brief, particle interactions are a heady mix of vibrating and interacting fields.
The concept of a classical particle is familiar. A particle is an object with an identifiable location. The object could be big or small, or it could have a peculiar shape. For a subatomic particle like an electron, the usual mental image is something akin to a microscopic ball. When particles interact, they can bounce off one another, like two billiard balls, or can merge, like two lumps of clay hitting one another.
Classical waves are equally familiar. Think of the up and down wiggles on the surface of a lake as a series of objects are dropped into it. Mathematically, a one-dimensional wave is just a steadily oscillating sinusoidal curve. It extends infinitely in either direction with a fixed, repeating wavelength. Unlike particles, waves have no identifiable location. Furthermore, waves interact very differently than particles. As two waves interact, they pass through one another, with the crests and troughs of the two waves either enhancing each other into a bigger crest or cancelling each other entirely (known as constructive and destructive interference, respectively).
A classical wave has an infinite length and no unique location. (Credit: Don Lincoln)
Given that traditional particles and waves seem to have such very different properties, it is easy to understand how early 20th century physicists were so confused as they tried to reconcile claims that things like photons and electrons were both particles and waves. However, scientists have come to understand that subatomic objects have both wave and particle properties, rather than existing as one or the other.
For example, an object like an electron has a wavelength, but it doesnt extend off to infinity. Instead, the amplitude (or height) of the wave has a location where it is maximized, and then it decreases at distances farther from the maximum. The result is what is called a wave packet. In the context of early 20th century quantum mechanics, the term wavicle was briefly in vogue, although it is now rarely used.
A wave packet is an accurate depiction of what a quantum particle is. It contains elements of both a wave and a particle. (Credit: Don Lincoln)
It is completely reasonable to think of subatomic particles like electrons and photons as wave packets, but given that waves are vibrations, one quickly asks, What exactly is it that is vibrating? or, equally confounding, What is the meaning of the wave packet? This is where things get a bit confusing.
In traditional quantum mechanics, this wave packet is called a wave function, and it is simply a method to calculate probabilities. If you square the wave function, the result is a function that tells you the likely locations where the particle will interact with other particles. This wave packet is merely a mathematical construct and nothing else.
When wave function (representing the wave packet) is squared, the result is a probability function that shows where the particle can and cannot be found. (Credit: Don Lincoln)
However, the situation becomes somewhat more physical when more modern ideas of quantum mechanics are used. The name for the modern theory describing particles is quantum field theory. Modern quantum field theory postulates that space is full of a series of fields. There is a field for each kind of known subatomic particle. For example, there is an electron field, a photon field, and so on. There are even quark fields.
According to this theory, an electron is nothing more than a wave packet in the electron field. The meaning of the wave packet is the same as in traditional quantum mechanics that is, if you square the wave function (representing the wave packet), the outcome is the probability of detecting an electron at that location.
The really neat thing about this understanding of particles is it gives us a very different mental picture of how particles are emitted and absorbed at the quantum level. For example, it is common for one subatomic particle to emit another, say, an electron emitting a photon. If subatomic particles are wave packets (localized vibrations of specific fields), then when an electron emits a photon, vibrations in the electron field are transferred to the photon field.
In a way, its like putting two identical tuning forks near one another and hitting one of them. The vibrations from that fork will transfer to the other, and soon both will be vibrating. In the quantum world, some of the vibrations of the electron field will transfer to the photon field, effectively creating a photon.
There is no question that modern physics theories can be difficult to envision.However, once you have embraced the idea that particles are little more than localized vibrations in several interacting fields, you have a reasonably accurate vision of how the quantum world works.
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What is a quantum particle really like? It's not what you think - Big Think
Research Fellow (Semiconductor Device Technology and in … – Times Higher Education
Job Description
A Research Fellow position is open in the research group of Dr. Gong Xiao, at the Department of Electrical and Computer Engineering, National University of Singapore (NUS). The Research Fellow will work closely with the Principal Investigator (PI) on one or more research projects. The project aims to explore advanced semiconductor electronic devices for future advanced integrated circuits and quantum technology.
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Location: Kent Ridge CampusOrganization: College of Design and EngineeringDepartment : Electrical and Computer EngineeringEmployee Referral Eligible: NoJob requisition ID : 22054
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Research Fellow (Semiconductor Device Technology and in ... - Times Higher Education
Nobel Prize winner to talk about science education research … – Cornell Chronicle
Nobel Prize-winning physicist Carl Wieman will visit campus Sept. 25-29 as an A.D. White Professor-at-Large, working with students and faculty and offering a public talk about his work in science education.
Wieman, professor of physics and education at Stanford University, won the Nobel Prize in 2001 for his work in atomic and optical physics. The focus of his talks at Cornell will be about his research and efforts to improve science education at the university level.
Cornells Active Learning Initiative (ALI), a program that gives grants to departments to help them introduce research-based teaching pedagogies into their curriculum, was modeled closely after initiatives created by Wieman at the University of Colorado and the University of British Columbia.
When I started working with Carl as a postdoc at the University of Colorado-Boulder, active-learning techniques was a new phrase at the college level and the field of discipline-based education research was just starting, said MichelleSmith,senior associate dean for undergraduate education in the College of Arts and Sciences and theAnn S. Bowers Professorof Ecology and Evolutionary Biology. Because of Carls vision and support, a new generation of college students at many universities experience learning in a whole new way. They come to class with their minds on, ready to solve problems, collaborate and apply their knowledge to novel scenarios.
Cornells Active Learning Initiative has given awards so far to 21 departments across the university, affecting almost 150 faculty teaching 100 courses to thousands of Cornell undergraduates each year.
Wiemans public talk, Teaching and Learning Science in the 21st Century, is scheduled for Sept. 26 at 4 p.m. in the Schwartz Auditorium in Rockefeller Hall. The event is free and open to the public.
Guided by experimental tests of theory and practice, science and engineering have advanced rapidly in the past 500 years. Education in these subjects, however, guided primarily by tradition and dogma, has remained largelyunchanged, Wieman said, describing his talk. Recent research is setting the stage for a new approach to teaching that can provide the relevant and effective science education for all students that is needed for the 21st century.
Wieman is also the founder of PhET, which provides online interactive simulations to help students learn science, and the author of Improving How Universities Teach Science: Lessons from the Science Education Initiative. He is currently studying expertise and problem-solving in science and engineering disciplines, and how this can be better measured and taught. Most recently, he was awarded the 2020 Yidan International Prize for Education Research.
Along with Wiemans public talk, he will be speaking at the Physics Colloquium on Sept. 25 at 4 p.m., also in Schwartz Auditorium. The topic of that talk is Teaching Students to Think Like Physicists. He will also be speaking at an event for West Campus students.
As a new graduate student being introduced to physics education research, I was particularly excited by Carls notion of taking a scientific approach to science education that I could use my physics training and my interests in physics research to study teaching and learning in physics, said Natasha Holmes, the Ann S. Bowers Associate Professor in the Department of Physics (A&S). It wasnt just that I needed to understand quantum mechanics in order to say something about how to teach quantum mechanics, but that I could also use the tools and methodologies for solving physics problems to solve physics education problems.
A.D. White Professors-at-Large are appointed for six-year terms and visit campus for approximately one week in each three-year period. There are currently 19 active Professors-at-Large, representing five disciplines.
Kathy Hovis is a writer for the College of Arts and Sciences.
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Nobel Prize winner to talk about science education research ... - Cornell Chronicle
Emanuele Berti and David Kaplan named Simons Investigators in … – The Hub at Johns Hopkins
ByRachel Wallach
Emanuele Berti and David Kaplan, both professors in the William H. Miller III Department of Physics and Astronomy, were named Simons Investigators in Physics by the Simons Foundation. Simons Investigators are outstanding theoretical scientists who receive a stable base of research support from the foundation, enabling them to undertake the long-term study of fundamental questions.
Image caption: David Kaplan and Emanuele Berti
Berti is a theoretical physicist who specializes in gravitational physics and gravitational-wave astronomy. His research interests include the structure, stability, dynamics, and formation of black holes and neutron stars; gravitational-wave signatures of modified theories of gravity and physics beyond the Standard Model; using gravitational waves to understand black hole binary astrophysics and cosmology; and preparing for the challenge of detecting gravitational waves in space with LISA (Laser Interferometer Space Antenna).
With the Simons funding, he plans to train Johns Hopkins students and postdocs in gravitational-wave physics and astronomy. "The models we use to detect gravitational waves from merging black holes and neutron stars are not perfect," Berti says. His group will work to improve these models, along with the ability to look for physics beyond general relativity. The group will use data from current gravitational-wave detectors to understand how astrophysical binaries of black holes and neutron stars form in the universe. The group will also explore the spectacular science enabled by future gravitational-wave detectors on the ground using the Cosmic Explorer and Einstein Telescope, and in space with LISA. These detectors will be much more sensitive, allowing researchers to use gravitational waves as messengers from the early universe.
Kaplan is also a theoretical physicist who discovers possible theoretical extensions to the standard models of particle physics and cosmology and finds novel ways to test them experimentally. He has discovered models of a naturally small cosmological constant and Higgs mass, classical solutions for firewalls in general relativity, and causal modifications of quantum mechanics. He has also found testable models of dark matter, dark energy, and dark radiation. He has proposed algorithms to discover both heavy and long-lived particles at colliders, as well as techniques for discovering dark matter and new elementary forces using new technologies in novel ways.The Simons funding will allow Kaplan to continue worldwide collaborations exploring some of the fundamentals of theoretical physics that could have dramatic physical consequences in cosmology. As Kaplan researches how gravity and quantum field theory interact, he has come to believe there may be deviations in quantum field theory itself. Discovering how general relativity emerges from a quantum theory has revealed the presence of an additional term in general relativity.
"In that sense, we're saying that there's a correction to Einstein's laws," Kaplan says. "And that correction, if it's there, would look like there is some dark matter in the universe that we can't interact with. That's what we're very excited and curious about and wanting to see if this is really true, and what the consequences of that are."
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Emanuele Berti and David Kaplan named Simons Investigators in ... - The Hub at Johns Hopkins
CERN Places New Limits In The Search For Magnetic Monopoles – IFLScience
Physicists suspect the universe contains magnetic monopoles north or south poles without their counterpart. Theyve yet to find them, but new data from the worlds most powerful particle collider has allowed them to tighten the limits on where in energy-space they may lie.
Every magnet we know, from the Earth itself down to tiny versions we attach to our fridges, has both a north and a south pole. Who hasnt spent time attempting to push two poles of the same sort together? For almost a century, physicists have been on what some may consider an even more fruitless task; finding a north (or south) pole that exists in isolation, with no counterpart.
It sounds like the product of a mind on drugs Hey, what if there was only one magnetic pole? but it was the famously taciturn and workaholic physicist Paul Dirac who proposed the existence of what he called magnetic monopoles. Dirac showed their presence was consistent with quantum mechanics, and indeed a single magnetic monopole, somewhere in the universe could explain otherwise inexplicable features of charge. Dirac proposed the smallest possible magnetic charge, including for a single pole, was 68.5 times the charge on an electron. All larger monopoles should be multiples of that.
In the 70s, the idea moved from possibility to probability, as the existence of magnetic monopoles came to be a key test for theories to unite general relativity and quantum mechanics. Wacky as they sound to those outside the field, one physicist named Joseph Polchinski called their existence; One of the safest bets one could make about physics not yet seen. That was 21 years ago, and Polchinskis bet remains unfilled reports of the discovery of magnetic monopoles have occurred occasionally, but then been withdrawn or cases of misreporting.
The ATLAS collaboration at CERN suspects there are two ways high energy collisions between protons may create magnetic monopoles with masses up to 4 TeV. Each relies on the protons releasing virtual photons (an intermediary between particles that carries the electromagnetic force). In one a virtual photon creates a magnetic monopole on its own, while in the other two photons interact to create a monopole. Either of these would, the collaboration notes; Restore the broken electric-magnetic dual symmetry in Maxwells equations.
ATLAS hopes to find evidence for one of these by looking for charge deposits on their detector. Since a monopole would need to carry a charge so much greater than that of an electron, its deposits should stand out from those of more familiar subatomic particles.
Large Hadron Collider (LHC) data takes a long time to analyze. ATLAS has only now released a preprint of a paper still to pass peer review based on the second LHC run, from 2015-2018. Although they have not found evidence of magnetic monopoles, the team believes they have narrowed down the possible masses/energies for the smallest magnetic monopoles, and their rate of production, by a factor of three.
Quests like this can seem endless to outsiders, as particle physicists report over and over not finding what they are looking for. Telling the world they have narrowed the limits can sound like a justification of failure. However, the same pattern was seen with the search for the Higgs Boson, eventually ending in stunning success. As with the Higgs, finding magnetic monopoles is important, not only to prove theories that predict their existence right, but because the masses we find would differentiate between competing theories.
Certainly, the physics community believes in the quest. The list of the members of the ATLAS collaboration lists more than 3,000 scientists, making their names and affiliations considerably longer than the paper itself.
The paper has been submitted to the Journal of High Energy Physics, and a preprint is available on ArXiv.org
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CERN Places New Limits In The Search For Magnetic Monopoles - IFLScience
University of Maryland and IonQ Celebrate Opening of QLab: A Hub … – StreetInsider.com
QLab offers researchers, students, professionals direct access to cutting-edge quantum computers
COLLEGE PARK, Md., Sept. 19, 2023 /PRNewswire/ --The University of Maryland (UMD) today announced the grand opening of the National Quantum Laboratory (QLab), a groundbreaking quantum research center developed in partnership with IonQ (NYSE: IONQ), a leader in the quantum computing industry. The QLab enables people from across the nation and around the world to develop and design quantum technologies on one of the world's most powerful quantum computers while working alongside leading experts in the field, in an effort to address the most complex challenges of our time.
Located inside UMD's Discovery District, this unique, cutting-edge workspace aims to build the next generation of quantum talent and innovations and further establish the region as the Capital of Quantum. Thanks to the nearly $20 million investment that fueled this facility's opening, researchers, students, industry leaders, entrepreneurs and others are already taking advantage of this collaboration to explore how quantum computers can help improve machine learning and AI, materials discovery, supply chain logistics, climate modeling, cybersecurity and more.
As a node in the Mid-Atlantic Regional Quantum Internet (MARQI), the QLab is also accelerating the development of quantum networking capabilities critical for realizing the full potential of quantum computers, sensors and communications systems. QLab actively supports the growth of a skilled quantum workforce and has hosted more than 300 participants in virtual and in-person workshops and bootcamps.
"We cannot fully imagine where quantum computing will take us in the future, but we do know the collaborations made possible through QLab will be essential to moving the field forward and reaching the life-altering discoveries we seek," said University of Maryland President Darryll J. Pines. "QLab spikes our competitiveness factor for the state and our region as we attract innovators from all over the world to work with us and share resources."
UMD is one of the world's leading institutions of quantum science and engineering, working in close partnership with the National Institute of Standards and Technology as well as other federal agencies and labs. The university boasts more than 200 quantum researchers, eight quantum-focused centers and a comprehensive suite of quantum education offerings.
This first-of-its-kind QLab builds upon the university's $300 million investment in quantum science and more than 30-year track record of driving advances in quantum physics and technology. It additionally marks the latest extension of the university's partnership with IonQ, a company partially founded on research conducted at UMD.
"At IonQ, we firmly believe that the future of quantum relies on a strong partnership between industry and academia. QLab is a testament of our commitment to nurturing this collaboration, paving the way for students to be at the forefront of quantum research and development," said Peter Chapman, CEO and president, IonQ. "Through our own journey from a research-oriented approach to our current focus on engineering and manufacturing, we aim to achieve an advanced quantum system in the near future that will deliver significant advantages over classical computing for certain use cases."
The QLab builds on and reinforces the strong, impact-focused regional collaborations enabled by the Mid-Atlantic Quantum Alliance (MQA) and its 38 members from academia, industry, and government.
IonQ will also be sharing new developments in quantum computing at the Quantum World Congress, which takes place September 27-28. To watch the livestream event, please RSVP here.
About the University of Maryland
The University of Maryland (UMD) is the state's flagship university and a leading public research institution, propelled by a $1.3 billion joint research enterprise. Located four miles from Washington, D.C., the university is dedicated to addressing the grand challenges of our time and is the nation's first Do Good campus. It is driven by a diverse and proudly inclusive community of more than 50,000 fearless Terrapins. UMD is a top producer of Fulbright scholars and offers an unparalleled student experience with more than 300 academic programs, 25 living-learning programs and 400 study abroad programs. Spurred by a culture of innovation and creativity, UMD faculty are global leaders in their field and include Nobel laureates, Pulitzer Prize winners and members of the national academies. For more information about the University of Maryland, visit umd.edu.
IonQ Forward-Looking Statements
This press release contains certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Some of the forward-looking statements can be identified by the use of forward- looking words, including the words "believe," "will," "aims," "seek," and other similar expressions. These statements include those related to the impact of the partnership between UMD and IonQ and of QLab; the future benefits of quantum computing and discoveries in quantum technologies; and the potential for a quantum system to deliver significant advantages over classical computing in the near future. Forward-looking statements are based on current expectations and assumptions and, as a result, are subject to risks and uncertainties. Many factors could cause actual future events to differ materially from the forward-looking statements in this press release, including but not limited to: the risks and uncertainties described in the "Risk Factors" section of IonQ's Quarterly Report on Form 10-Q for the quarter ended June 30, 2023, and other documents filed by IonQ from time to time with the Securities and Exchange Commission. Forward-looking statements speak only as of the date they are made. Readers are cautioned not to put undue reliance on forward-looking statements, and IonQ assumes no obligation and does not intend to update or revise these forward-looking statements, whether as a result of new information, future events, or otherwise. IonQ does not give any assurance that it will achieve its expectations.
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New clues to the nature of elusive dark matter – Science Daily
A team of international researchers, led by experts at the University of Adelaide, has uncovered further clues in the quest for insights into the nature of dark matter.
"Dark matter makes up 84 per cent of the matter in the universe but we know very little about it," said Professor Anthony Thomas, Elder Professor of Physics, University of Adelaide.
"The existence of dark matter has been firmly established from its gravitational interactions, yet its precise nature continues to elude us despite the best efforts of physicists around the world."
"The key to understanding this mystery could lie with the dark photon, a theoretical massive particle that may serve as a portal between the dark sector of particles and regular matter."
Regular matter, of which we and our physical world are made up of, is far less abundant than dark matter: five times more dark matter exists than regular matter. Finding out more about dark matter is one of the greatest challenges for physicists around the world.
The dark photon is a hypothetical hidden sector particle, proposed as a force carrier similar to the photon of electromagnetism but potentially connected to dark matter. Testing existing theories about dark matter is one of the approaches that scientists such as Professor Thomas, along with colleagues Professor Martin White, Dr Xuangong Wang and Nicholas Hunt-Smith, who are members of the Australian Research Council (ARC) Centre of Excellence for Dark Matter Particle Physics, are pursuing in order to gain more clues into this elusive but highly important substance.
"In our latest study, we examine the potential effects that a dark photon could have on the complete set of experimental results from the deep inelastic scattering process," said Professor Thomas.
Analysis of the by-products of the collisions of particles accelerated to extremely high energies gives scientists good evidence of the structure of the subatomic world and the laws of nature governing it.
In particle physics, deep inelastic scattering is the name given to a process used to probe the insides of hadrons (particularly the baryons, such as protons and neutrons), using electrons, muons and neutrinos.
"We have made use of the state-of-the-art Jefferson Lab Angular Momentum (JAM) parton distribution function global analysis framework, modifying the underlying theory to allow for the possibility of a dark photon," said Professor Thomas.
"Our work shows that the dark photon hypothesis is preferred over the standard model hypothesis at a significance of 6.5 sigma, which constitutes evidence for a particle discovery."
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New clues to the nature of elusive dark matter - Science Daily
First Light for a Next-Generation Light Source – Physics
September 19, 2023• Physics 16, 160
The Linac Coherent Light Source, an x-ray free-electron laser at SLAC National Accelerator Laboratory, lights up for the first time after an upgrade that should allow it to deliver up to one million x-ray pulses per second.
G. Stewart/SLAC National Accelerator Laboratory
G. Stewart/SLAC National Accelerator Laboratory
X-ray free-electron lasers (XFELs) first came into existence two decades ago. They have since enabled pioneering experiments that see both the ultrafast and the ultrasmall. Existing devices generate short and intense x-ray pulses at a rate of around 100 x-ray pulses per second. But one of these facilities, the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory in California, is set to eclipse this pulse rate. The LCLS Collaboration has now announced first light for its upgraded machine, LCLS-II. When it is fully up and running, LCLS-II is expected to fire one million pulses per second, making it the worlds most powerful x-ray laser.
The LCLS-II upgrade signifies a quantum leap in the machines potential for discovery, says Robert Schoenlein, the LCLSs deputy director for science. Now, rather than demonstration experiments on simple, model systems, scientists will be able to explore complex, real-world systems, he adds. For example, experimenters could peer into biological systems at ambient temperatures and physiological conditions, study photochemical systems and catalysts under the conditions in which they operate, and monitor nanoscale fluctuations of the electronic and magnetic correlations thought to govern the behavior of quantum materials.
The XFEL was first proposed in 1992 to tackle the challenge of building an x-ray laser. Conventional laser schemes excite large numbers of atoms into states from which they emit light. But excited states with energies corresponding to x-ray wavelengths are too short-lived to build up a sizeable excited-state population. XFELs instead rely on electrons traveling at relativistic speed through a periodic magnetic array called an undulator. Moving in bunches, the electrons wiggle through the undulator, emitting x-ray radiation that interacts with other bunches and becomes amplified. The result is a bright x-ray beam with laser coherence.
The first XFEL was built in Hamburg, Germany, in 2005. Today that XFEL emits soft x-ray radiation, which has wavelengths as short as a few nanometers. LCLS switched on four years later and expanded XFELs reach to the much shorter wavelengths of hard x rays, which are essential to atomic-resolution imaging and diffraction experiments. These and other facilities that later appeared in Japan, Italy, South Korea, Germany, and Switzerland have enabled scientists to probe catalytic reactions in real time, solve the structures of hard-to-crystallize proteins, and shed light on the role of electronphoton coupling in high-temperature superconductors. The ability to record movies of the dynamics of molecules, atoms, and even electrons also became possible because x-ray pulses can be as short as a couple of hundred attoseconds.
The upgrades to LCLS offer a new mode of XFEL operation, in which the facility delivers an almost continuous x-ray beam in the form of a megahertz pulse train. For the original LCLS, the pulse rate, which maxed out at 120 Hz, was set by the properties of the linear accelerator that produced the relativistic electrons. Built out of copper, a conventional metal, and operated at room temperatures, the accelerator had to be switched on an off 120 times per second to avoid heat-induced damage. In LCLS-II some of the copper has been replaced with niobium, which is superconducting at the operating temperature of 2 K. Bypassing the damage limitations of copper, the dissipationless superconducting elements allow an 8000-fold gain in the maximum repetition rate. The new superconducting technology is also expected to reduced jitter in the beam, says LCLS director Michael Dunne. Greater stability and reproducibility, higher repetition rate, and increased average power will transform our ability to look at a whole range of systems, he adds.
LCLS-II is a boon for time-resolved chemistry-focused experiments, says Munira Khalil, a physical chemist at the University of Washington in Seattle. Khalil, a user of LCLS, plans to take advantage of the photon bounty of the dynamical experiments. She hopes such experiments may fulfill a chemists dream: real-time observations of the coupled motion of atoms and electrons. With extra photons, scientists could also probe dilute samples, potentially shedding light on how metals bind to specific sites in proteinsa process relevant to the function of half of all of natures proteins.
The megahertz pulse rate also means that experiments that previously took days to perform could now be completed in hours or minutes, says Henry Chapman of the Center for Free Electron Laser Science at DESY, Germany. At LCLS and later at Hamburgs XFEL, Chapman ran pioneering experiments to determine the structures of proteins. The method he used, called serial crystallography, involves merging the diffraction patterns of multiple samples sequentially injected into the XFELs beam. Serial crystallography has allowed scientists to determine the structures of biologically relevant proteins that form crystals too small to study with conventional crystallography techniques. Chapman says that the increased throughput enabled by LCLS-II will permit much more ambitious experiments, such as measurements of biomolecular reactions on timescales from femtoseconds to microseconds. One could also think of an on the fly analysis that feeds back into the experiment to discover optimal conditions for drug binding or catalysis, he says.
For Khalil, the dramatic speedup of the experiments is a key advance of LCLS-II, as she thinks it will make these kinds of experiments accessible to a wider group of people. Until now, she says, XFEL facilities were mostly used by people who had the opportunity to work extensively at XFELs as postdocs or graduate students. Many more experimenters should now be able to enter the XFEL arena, she says. Its an exciting time for the field.
Matteo Rini
Matteo Rini is the Editor of Physics Magazine.
The slow drift of microscale features on a surface reveals the force driving atoms from the hot to the cold side of the material. Read More
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