UMD Physics Offers Undergraduates New Research Opportunities with FIRE

FIRE20192019 FIRE Simulating Particle Detection students with their research leader, Dr. Muge Karagoz.

The University of Maryland’s Physics Department has joined The First-Year Innovation & Research Experience (FIRE) program through the launch of the Simulating Particle Detection research group. The group is run by Dr. Muge Karagoz in collaboration with two Experimental High Energy Physics faculty members: Professor Sarah Eno and Assistant Professor Alberto Belloni, both of whom are members of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider based at CERN in Geneva, Switzerland.

FIRE is a three-semester program with second and third semesters concentrating on research in a specific discipline. FIRE provides students with authentic research experience and a broad mentorship with the goal of influencing academic success and personal development. The FIRE Simulating Particle Detection brings undergraduate students from a wide variety of majors into the field of experimental particle physics, concentrating on the simulation of cutting-edge, high-energy particle detectors, such as the planned upgrade of the CMS detector.

In Simulating Particle Detection, students go through all aspects of conducting research. They start with a literature search on particle physics and detectors, as well as training on computing and coding. They then move on to data analysis and presentation of their results. For their research projects, they form teams giving them a chance to experience the pursuit of collaborative achievements. As a natural outcome of performing research, especially in the context of an international, big-data experiment like CMS, the students also learn skills such as adaptability, and strategies such as trouble-shooting.

The research group launched in the spring of 2019, with 33 undergraduate students, and has just completed its first semester. This was made possible through the collaborative efforts of the FIRE program operated through the Office of the Senior Vice President and the Provost, the Department of Physics, and the Experimental High Energy Physics Group. The research group was also greatly helped by highly-dedicated undergraduate research assistants and peer mentors. Peer Mentors are second-year FIRE students who return to serve as mentors for the first-year students in FIRE research groups, through the Teaching and Learning Transformation Center’s Academic Peer Mentoring Program. The Simulating Particle Detection will continue with current students in the fall, with the next group of first-year participants to begin in Spring 2020.

More information on the Simulating Particle Detection research group can be found on the FIRE program’s web site (http://fire.umd.edu/). Additional information on the Experimental High Energy Physics Group can be found on the Department of Physics website (https://umdphysics.umd.edu/research/research-areas/high-energy-physics.html).

Letters From a Science Giant

Auction of Notes by Stephen Hawking to Professor Emeritus Charles Misner Endow the Weber Fund with Approximately $260,000

Hawking Memorabilia 02262019 4976 1920x1080A handwritten letter from famed physicist Stephen Hawking to UMD physics Professor Emeritus Charles Misner in the late 1960s is one of the items being auctioned to create an endowment to support study in the field both specialized in—gravitational physics. (Photo by John T. Consoli)

"Dear Charlie,” each letter begins.

They go on to talk about kids, explore recent theoretical ideas and even ask whether reimbursement for a recent trip to the University of Maryland was coming through. Job references are also a big topic—typical for correspondence between two academics.

Far from typical was their author: Stephen Hawking, the brilliant physicist who became a popular author, a science advocate and an international symbol of perseverance in the face of his crippling Lou Gehrig’s disease.

Now the letters—donated by their recipient, UMD physics Professor Emeritus Charles Misner—are being auctioned to create an endowment in the College of Computer, Mathematical, and Natural Sciences.  

Hawking wrote the letters between 1967 and 1970. He’d hit it off with Misner, a fellow physicist studying Einstein’s theory of gravitation, while the American scientist was on a fellowship at the University of Cambridge.

Soon after, Hawking brought his family to Maryland to stay at Misner’s home and spend time at UMD. Misner’s research group was immersed in the theoretical study of gravitation, while UMD Physics Professor Joseph Weber was leading a charge to experimentally detect gravitational waves in space-time—something predicted by Einstein’s theory that even Einstein doubted could be found.

In correspondence that followed the visit, among other things, Hawking asked Misner for job referrals. “Not that I was smarter than him—but I was older,” Misner cracked in a recent interview.

Even in the late ’60s, despite the increasing physical limitations brought on by his ALS, it was clear Hawking was headed for greatness, Misner said. Through the years, the two and their families continued meeting up during fellowships, at conferences and elsewhere, although communication for Hawking became more and more labored, Misner said. Hawking died in March 2018.

Last year, when the Department of Physics was seeking funds for a memorial to Weber—who failed in his personal quest to observe gravitational waves, but laid the critical groundwork for a later experiment that would succeed—Misner remembered the letters. Departmental staff helped ransack his overstuffed office, finally turning up four letters that were auctioned by Christie's, which will create an endowment in honor of Weber to support research in gravitational physics. The auction just closed on May 23, 2019, and the letters sold for a total of 228,750 GBP.  After commissions, this should endow the Weber fund with approximately $260,000.

Original story by Chris Carroll here.

High-resolution Imaging Technique Maps out an Atomic Wave Function

Overlapping Laser Beams Offer a New Way to Extract A Quantum System's Essential Information

19pml013 wavefunction porto rolston 2mbThe team has used laser light to construct an image of an atomic wave function (shown in purple). The graphic is an artistic depiction of this process, showing a microscope objective trained on atoms (spheres) suspended in an optical lattice (tall white waves). The team's technique reveals information about an atomic wave function in unprecedented detail.

From NIST News

JQI researchers have demonstrated a new way to obtain the essential details that describe an isolated quantum system, such as a gas of atoms, through direct observation. The new method gives information about the likelihood of finding atoms at specific locations in the system with unprecedented spatial resolution. With this technique, scientists can obtain details on a scale of tens of nanometers—smaller than the width of a virus.

The new experiments use an optical lattice—a web of laser light that suspends thousands of individual atoms—to determine the probability that an atom might be at any given location. Because each individual atom in the lattice behaves like all the others, a measurement on the entire group of atoms reveals the likelihood of an individual atom to be in a particular point in space.  

Published in the journal Physical Review X, the technique (similar work was published simultaneously by a group at the University of Chicago) can yield the likelihood of the atoms’ locations at well below the wavelength of the light used to illuminate the atoms—50 times better than the limit of what optical microscopy can normally resolve. 

“It’s a demonstration of our ability to observe quantum mechanics,” says JQI Fellow and NIST physicist Trey Porto, one of the researchers behind the effort. “It hasn’t been done with atoms with anywhere near this precision.”

To understand a quantum system, physicists talk frequently about its “wave function.” It is not just an important detail; it’s the whole story. It contains all the information you need to describe the system.   

“It’s the description of the system,” says JQI Fellow and UMD physics professor Steve Rolston, another of the paper’s authors. “If you have the wave function information, you can calculate everything else about it—such as the object’s magnetism, its conductivity and its likelihood to emit or absorb light.”

While the wave function is a mathematical expression and not a physical object, the team’s method can reveal the behavior that the wave function describes: the probabilities that a quantum system will behave in one way versus another. In the world of quantum mechanics, probability is everything. 

Among the many strange principles of quantum mechanics is the idea that before we measure their positions, objects may not have a pinpointable location. The electrons surrounding the nucleus of an atom, for example, do not travel in regular planetlike orbits, contrary to the image some of us were taught in school. Instead, they act like rippling waves, so that an electron itself cannot be said to have a definite location. Rather, the electrons reside within fuzzy regions of space.

All objects can have this wavelike behavior, but for anything large enough for unaided eyes to see, the effect is imperceptible and the rules of classical physics are in force—we don’t notice buildings, buckets or breadcrumbs spreading out like waves. But isolate a tiny object such as an atom, and the situation is different because the atom exists in a size realm where the effects of quantum mechanics reign supreme. It’s not possible to say with certainty where it’s located, only that it will be found somewhere. The wave function provides the set of probabilities that the atom will be found in any given place. 

Quantum mechanics is well-enough understood—by physicists, anyway—that for a simple-enough system, experts can calculate the wave function from first principles without needing to observe it. Many interesting systems are complicated, though.

“There are quantum systems that can’t be calculated because they are too difficult,” Rolston says—such as molecules made of several large atoms. “This approach could help us understand those situations.”

As the wave function describes only a set of probabilities, how can physicists get a complete picture of its effects in short order? The team’s approach involves measuring a large number of identical quantum systems at the same time and combining the results into one overall picture. It’s sort of like rolling 100,000 pairs of dice at the same time—each roll gives a single result, and contributes a single point on the probability curve showing the values of all the dice. 

What the team observed were the positions of the roughly 100,000 atoms of ytterbium the optical lattice suspends in its lasers. The ytterbium atoms are isolated from their neighbors and restricted to moving back and forth along a one-dimensional line segment. To get a high-resolution picture, the team found a way to observe narrow slices of these line segments, and how often each atom showed up in its respective slice. After observing one region, the team measured another, until it had the whole picture.

Rolston says that while he hasn’t yet thought of a “killer app” that would take advantage of the technique, the mere fact that the team has directly imaged something central to quantum research fascinates him. 

“It’s not totally obvious where it will be used, but it’s a new technique that offers new opportunities,” he said. “We’ve been using an optical lattice to capture atoms for years, and now it’s become a new kind of measurement tool.” 

The original story was written by C. Boutin/NIST. Minor modifications were made for posting to this website.

Professors Chris Monroe and Jake Taylor Describe the National Quantum Initiative in Science Magazine

F1.largeA semiconductor chip ion trap, fabricated by Sandia National Laboratories, is composed of gold-plated electrodes that suspend individual atomic ion qubits above the surface of the chip. The chip (bow-tie shape) is about 10 mm across. The inset is a magnified image of 80 atomic 171Yb+ ions glowing from scattered laser radiation. PHOTO: KAI HUDEK/UMD/IONQ AND E. EDWARDS/JQIUMD physics professors Christopher Monroe and Jake Taylor, together with Michael Raymer of the University of Oregon, published an article on the National Quantum Initiative (NQI) in the May 3 issue of Science. The NQI Act, which was signed into law on December 21, 2018, lays out a plan for the National Institute of Standards and Technology, the National Science Foundation, and the Department of Energy to work with academia and industry to further grow the quantum information science and technology (QIST) sector. Earlier this year, Monroe and Raymer wrote an article on the NQI for the February 2019 issue of Quantum Science and Technology, which details some of the events that ultimately led to this law.

The new article describes how the NQI aims to enable a so-called QIST ecosystem to study and overcome scientific challenges in this area, as well as build up a workforce educated in quantum science. Some of the possible outcomes of the NQI could include improved sensors, universally programmable quantum computers, and a more secure global communication network. The article also briefly summarizes possible risks associated with quantum research and development, including possible failure modes of the technology, as well as unforeseen ethical questions.

Monroe is the Bice-Seci Zorn Professor of Physics, a Distinguished University Professor, Fellow of the Joint Quantum Institute (JQI) and the Joint Center for Quantum Information and Computer Science (QuICS). He also co-founded the quantum computing company IonQ. Monroe previously advocated for a NQI through the National Photonics Initiative and testified before a joint congressional committee hearing on the topic of American Leadership in Quantum Technology in 2017. A second JQI and QuICS Fellow Carl Williams, who is Acting Director of the Physical Measurement Laboratory at NIST, provided expert testimony to congress at that same hearing.

Taylor is an adjunct professor in the Department of Physics, Co-Director of the Joint Center for Quantum Information and Computer Science and Fellow of the Joint Quantum Institute and the National Institute of Standards and Technology. He is also the Assistant Director for Quantum Information Science at the Office of Science and Technology Policy and was recently named the Interim Director for the National Quantum Coordination Office, which was established as part of the NQI.

Raymer is a Knight Professor of Liberal Arts and Sciences of the Oregon Center for Optical, Molecular and Quantum Science at the University of Oregon. Raymer has also been a strong advocate for developing a national strategy around QIST.