Gorshkov Named APS Fellow

Adjunct Associate Professor Alexey Gorshkov has been elected as a Fellow of the American Physical Society (APS). He is one of 163 APS members to join the select group this year.Alexey GorshkovAlexey Gorshkov

Gorshkov, who is also a Fellow of the Joint Quantum Institute, a Physicist at the National Institute of Standards and Technology, and a Fellow of the Joint Center for Quantum Information and Computer Science, leads a theoretical research group with interests that span many areas of physics. He and his team study everything from single atoms and pinpoints of light to information speed limits and exotic phases of matter. And they often investigate all of it through the lens of quantum information theory.

Each year, APS selects no more than 0.5% of its non-student membership—currently more than 33,000 people—as fellows, a recognition by peers of their contributions to physics. Gorshkov was nominated for his “contributions to the understanding, design, and control of quantum many-body atomic, molecular, and optical systems and their applications to phase transitions, entanglement generation and propagation, synthetic magnetism, and quantum memory and simulation.”

Quantum Matchmaking: New NIST System Detects Ultra-Faint Communications Signals Using the Principles of Quantum Physics

Researchers at the National Institute of Standards and Technology (NIST), the Department of Physics at the University of Maryland (UMD) and JQI have devised and demonstrated a system that could dramatically increase the performance of communications networks while enabling record-low error rates in detecting even the faintest of signals. The work could potentially decrease the total amount of energy required for state-of-the-art networks by a factor of 10 to 100. 

The proof-of-principle system consists of a novel receiver and corresponding signal-processing technique that, unlike the methods used in today’s networks, are entirely based on the properties of quantum physics and thereby capable of handling even extremely weak signals with pulses that carry many bits of data.The incoming signal (red, lower left) proceeds through a beam splitter to the photon detector, which has an attached time register (top right). The receiver sends the reference beam to the beam splitter to cancel the incoming pulse so that no light is detected. If even one photon is detected, it means that the receiver used an incorrect reference beam, which needs to be adjusted. The receiver uses exact times of photon detection to arrive at the right adjustment with fewer guesses. The combination of recorded detection times and the history of reference beam frequencies are used to find the frequency of the incoming signal. (Credit: NIST)The incoming signal (red, lower left) proceeds through a beam splitter to the photon detector, which has an attached time register (top right). The receiver sends the reference beam to the beam splitter to cancel the incoming pulse so that no light is detected. If even one photon is detected, it means that the receiver used an incorrect reference beam, which needs to be adjusted. The receiver uses exact times of photon detection to arrive at the right adjustment with fewer guesses. The combination of recorded detection times and the history of reference beam frequencies are used to find the frequency of the incoming signal. (Credit: NIST)

“We built the communication test bed using off-the-shelf components to demonstrate that quantum-measurement-enabled communication can potentially be scaled up for widespread commercial use,” said Ivan Burenkov, a research scientist at JQI. Burenkov and his colleagues report the results in Physical Review X Quantum(link is external). “Our effort shows that quantum measurements offer valuable, heretofore unforeseen advantages for telecommunications leading to revolutionary improvements in channel bandwidth and energy efficiency.”

Modern communications systems work by converting information into a laser-generated stream of digital light pulses in which information is encoded—in the form of changes to the properties of the light waves—for transfer and then decoded when it reaches the receiver. The train of pulses grows fainter as it travels along transmission channels, and conventional electronic technology for receiving and decoding data has reached the limit of its ability to precisely detect the information in such attenuated signals.

The signal pulse can dwindle until it is as weak as a few photons—or even less than one on average. At that point, inevitable random quantum fluctuations called “shot noise” make accurate reception impossible by normal (“classical,” as opposed to quantum) technology because the uncertainty caused by the noise makes up such a large part of the diminished signal. As a result, existing systems must amplify the signals repeatedly along the transmission line, at considerable energy cost, keeping them strong enough to detect reliably. 

The NIST team’s system can eliminate the need for amplifiers because it can reliably process even extremely feeble signal pulses: “The total energy required to transmit one bit becomes a fundamental factor hindering the development of networks,” said Sergey Polyakov, senior scientist on the NIST team and an adjunct associate professor of physics at UMD. “The goal is to reduce the sum of energy required by lasers, amplifiers, detectors, and support equipment to reliably transmit information over longer distances. In our work here we demonstrated that with the help of quantum measurement even faint laser pulses can be used to communicate multiple bits of information—a necessary step towards this goal.”

To increase the rate at which information can be transmitted, network researchers are finding ways to encode more information per pulse by using additional properties of the light wave. So a single laser light pulse, depending on how it was originally prepared for transmission, can carry multiple bits of data. To improve detection accuracy, quantum-enhanced receivers can be fitted onto classical network systems. To date, those hybrid combinations can process up to two bits per pulse. The NIST quantum system uses up to 16 distinct laser pulses to encode as many as four bits.

To demonstrate that capability, the NIST researchers created an input of faint laser pulses comparable to a substantially attenuated conventional network signal, with the average number of photons per pulse from 0.5 to 20 (though photons are whole particles, a number less than one simply means that some pulses contain no photons). 

After preparing this input signal, the NIST researchers take advantage of its wavelike properties, such as interference, until it finally hits the detector as photons (particles). In the realm of quantum physics, light can act as either particles (photons) or waves, with properties such as frequency and phase (the relative positions of the wave peaks). 

Inside the receiver, the input signal’s pulse train combines (interferes) with a separate, adjustable reference laser beam, which controls the frequency and phase of the combined light stream. It is extremely difficult to read the different encoded states in such a faint signal. So the NIST system is designed to measure the properties of the whole signal pulse by trying to match the properties of the reference laser to it exactly. The researchers achieve this through a series of successive measurements of the signal, each of which increases the probability of an accurate match.

That is done by adjusting the frequency and phase of the reference pulse so that it   interferes destructively with the signal when they are combined at the beam splitter, canceling the signal out completely so no photons can be detected. In this scheme, shot noise is not a factor: Total cancellation has no uncertainty. 

Thus, counterintuitively, a perfectly accurate measurement results in no photon reaching the detector. If the reference pulse has the wrong frequency, a photon can reach the detector. The receiver uses the time of that photon detection to predict the most probable signal frequency and adjusts the frequency of the reference pulse accordingly. If that prediction is still incorrect, the detection time of the next photon results in a more accurate prediction based on both photon detection times, and so on. 

“Once the signal interacts with the reference beam, the probability of detecting a photon varies in time,” Burenkov said, “and consequently the photon detection times contain information about the input state. We use that information to maximize the chance to guess correctly after the very first photon detection.

“Our communication protocol is designed to give different temporal profiles for different combinations of the signal and reference light. Then the detection time can be used to distinguish between the input states with some certainty. The certainty can be quite low at the beginning, but it is improved throughout the measurement. We want to switch the reference pulse to the right state after the very first photon detection because the signal contains just a few photons, and the longer we measure the signal with the correct reference, the better our confidence in the result is.”

Polyakov discussed the possible applications. “The future exponential growth of the internet will require a paradigm shift in the technology behind communications,” he said. “Quantum measurement could become this new technology. We demonstrated record low error rates with a new quantum receiver paired with the optimal encoding protocol. Our approach could significantly reduce energy for telecommunications.”

This story was originally published by NIST News(link is external). It has been adapted with minor changes here. JQI is a research partnership between UMD and NIST, with the support and participation of the Laboratory for Physical Sciences.

Reference publication: "Time-Resolving Quantum Measurement Enables Energy-Efficient, Large-Alphabet Communication," I.A. Burenkov, M.V. Jabir, A. Battou, S.V. Polyakov, PRX Quantum, 1, 010308 (2020)

Alumnus Douglas Arion Points to Mountains of Stars

Ever since he completed his Ph.D. at the University of Maryland, Douglas Arion (M.S. ’80, Ph.D. ’84, physics) has been an innovator. He has always enjoyed the challenge of building things from the ground up—houses (he designed two), groundbreaking technology, unique academic programs and even college sports teams. 

“I think I’m inventive and creative and have always wanted to build and make things that aren’t what’s expected,” Arion said. “I’ve always been somebody who wants to make stuff happen.”

Douglas Arion. Photo by Rebecca SteevesDouglas Arion. Photo by Rebecca SteevesAnd for 35-plus years, he’s been doing just that, thanks to his strong foundation in physics.

“If you understand physics you understand everything, because everything fundamentally is based on physics,” Arion said. “I don’t think there’s been a discipline I’ve worked in or a technology that I’ve worked on or used or a field that you can’t apply it to. If you understand physics, you can do anything.”

At UMD, Arion’s Ph.D. research was a complex blend of plasma physics, quantum mechanics and astrophysics. 

“I found a way to quickly determine when a magnetic field can rapidly change shape and  break—such as when there’s a flare on the sun,” Arion said.

Arion had plenty of inspiration. His friends and study partners included Penrose “Parney” Albright (M.S. ’82, Ph.D. ’85, physics), who went on to become assistant secretary of the U.S. Department of Homeland Security, and David Douglas (M.S. ’82, Ph.D. ’82, physics), who spent 35 years exploring the nature of matter as a senior scientist at Jefferson Lab in Virginia.

“The folks who graduated with me have gone on to do some really amazing things,” Arion said. “We were good friends. I still stay in touch with many of them today.”

Arion would begin making his own mark as an innovator soon after he left Maryland, when a connection he made on campus led to a job at Science Applications Incorporated (SAI), a Virginia-based defense contractor.

“I was first involved in modeling and analysis of radiation effects on spacecraft and missile systems, that was the first big project we worked on,” Arion said. “I ended up working on a whole bunch of different defense-related projects in radiation areas.”

Climbing through the ranks at SAI to assistant vice president, Arion led the design and testing of systems including space-qualified optics and high-precision structural measuring systems for more than a decade.

Then in 1994, he moved on to a completely different kind of challenge, inspired by an ad he saw for a unique position in academia—an endowed chair in science and technology entrepreneurship at Carthage College in Kenosha, Wisconsin.

“Carthage had received a donation from an alum, a former chem major, who said, ‘You need to start a program to teach science students how to launch ventures and how to run things,’” Arion explained. “So, I put in a resume and got hired. I built the country’s first program for undergraduates in science and technology entrepreneurship. And that was before it was sexy—you know, everybody has a program now. “

For Arion, it was another opportunity to build something from the ground up—this time, a program to teach science students the things they weren’t learning in the traditional college curriculum.

“When I created it, I started out saying in my head and then on paper, what’s all the stuff I wish someone had told me before I became a corporate exec, because there was a lot of stuff I had to learn on the fly,” Arion recalled.

Soon, Arion was teaching his students everything from personal finance and retirement planning to accounting, intellectual property and regulatory issues for business—all while coaching the college’s hockey team. His groundbreaking science entrepreneur program was so successful that it became a model for similar programs at colleges and universities around the country. 

In 2015, Arion’s efforts were recognized by his peers. Elected as a Fellow of the American Physical Society, he was honored for “groundbreaking work towards improving the educational impact of the physics degree by promoting the widespread adoption of entrepreneurship training and mindset within the discipline.”

Arion enjoyed academic life in Wisconsin, but as time went on, he missed the wild beauty of the New Hampshire mountains, where he spent summers hiking and biking as a boy. Arion never lost his love for the outdoors—or his passion for protecting the environment. And after more than a decade at Carthage College, he saw an opportunity to take his innovative energy—and science education—in a new direction.

“I’ve always been very unhappy with the general understanding of science in this country, and in particular when it comes to the environment,” Arion explained. “I wanted to do something different.”

His plan was to reinvent environmental education and change the way people see their place in the world around them.

“From my perspective, most people in western culture think that human beings are more important than everything else,” he said. “We look at every resource as something we can just take. If we’re more aware of our place in the universe we will become more protective of the resources that are all around us.”

That idea was the inspiration for Mountains of Stars, a program Arion launched in 2012 with a simple mission.

“We call it environmental awareness from a cosmic perspective,” he said.

mountains of stars logoFunded by the National Science Foundation and other supporters, Mountains of Stars began as a partnership between Carthage College and the Appalachian Mountain Club, the oldest outdoor recreation, conservation and education organization in the U.S. The mission: use high-quality, hands-on astronomy experiences to change people’s attitudes and actions toward the environment.

Why astronomy?

“Two things. One: It’s actually the only science. Because everything is part of it,” Arion explained. “You can address and integrate and incorporate everything that’s out there, all of the processes that have brought us to this point cosmically. It’s all one system—geological processes, natural biology, it’s everything. The second aspect is that people like it. If you have a telescope, people want to look through it. That gives you an opportunity to talk about something.”

Through the Mountains of Stars program, college physics and astronomy students train to be better science communicators and can then become part of the program’s environmental outreach, which includes hands-on astronomy and nature activities designed to engage the public and raise environmental awareness, one person at a time. Over nine years, the program has reached more than 65,000 people.

“I hope, over the long term, that we're planting enough seeds that people will actually change what they do and thus change the course of human behavior,” Arion explained. “I know it takes time, but you have to start somewhere.”

Arion is technically retired now, living on the doorstep of a national forest in a New Hampshire home he designed and taking full advantage of the outdoor lifestyle that goes with it. He still does research and leads entrepreneurship workshops around the world, and he is also involved in environmental initiatives like the international Dark-Sky Association. But it’s Mountains of Stars, the mission closest to Arion’s heart, that continues to get most of his time and energy. He hopes over time, the program can make the kind of difference that matters. 

“This is the thing that’s most important to me right now,” Arion said. “I hope in the future, someone looks back at it and says we did something good here.”

Written by Leslie Miller

Faculty, Staff, Student and Alumni Awards & Notes  

We proudly recognize members of our community who recently garnered major honors, authored books, began new positions and more.

Faculty and Staff 
Students
Alumni
Department Notes
  • The Department participated in the American Institute of Physics Task Force to Elevate African American representation in Undergraduate Physics & Astronomy (TEAM-UP). College Park Professor Jim Gates and College of Education Professor Sharon Fries-Britt served on the task force. 
  •  UMD & NIST hosted a Conference of Undergraduate Women in Physics (CUWiP) in January. 
  • The Maryland Quantum Alliance—a regional consortium of quantum scientists and engineers from across academia, national laboratories and industry—launched in January. Recently, it was expanded as the Mid-Atlantic Quantum Alliance. 
  • Research by a team that includes Assistant Professor Norbert Linke, Graduate Student Nhung Hong Nguyen, and Visiting Graduate Student Cinthia Huerta Alderete was selected as one of the 2019 Top Picks in Computer Architecture by IEEE Micro
  • The Condensed Matter Theory Center launched a blog
  • The Statistical Research Center of the American Institute of Physics found that the department is a top producer of physics undergraduate degrees
  • Negar Heidarian Boroujeni, Dave Buehrle, Tom Gleason, Jordan Goodman, Carter Hall, Kara Hoffman and Ted Jacobson received campus funding to adapt instructional methods in the wake of the coronavirus.  
  • The Quantum Technology Center (QTC)—a joint venture between the A. James Clark School of Engineering and the College of Computer, Mathematical, and Natural Sciences—today entered into an education partnership agreement with the U.S. Naval Research Laboratory (NRL) to identify and pursue quantum technology research opportunities.