Author: Victoria Kabakian

New federal awards highlight Brown’s quantum expertise across academic departments

Victoria Kabakian Uncategorized

By harnessing the often-strange behavior of matter at the tiniest scales, quantum technologies could open the door to ultra-fast computers, new kinds of sensors, uncrackable information security and other revolutionary technologies.

This academic year, Brown researchers have won four new federal grants — totaling well over $6 million — to study exotic quantum states and materials that will power these next-generation devices. The awards are a testament to the expertise in quantum science across Brown’s faculty and the University’s ability to bring those people together, said Gang Xiao, physics department chair and principal investigator on one of the new grants.

“Brown has great strength in quantum science, particularly in theoretical research, in device design and materials development,” Xiao said. “The synergy among faculty is further leveraged by the efforts of Brown’s research office, which has organized a series of events for faculty to brainstorm and to execute on our quantum objectives. Strength and collaboration have allowed us to capitalize on funding opportunities.”

The grants are part of a push by U.S. science agencies to develop new quantum technologies and make new discoveries. In early 2019, President Donald Trump signed into law the National Quantum Initiative Act, a multi-agency program to support research and training in quantum information science. The initiative builds on other quantum science programs at the National Science Foundation (NSF) and other agencies.

Brown’s funding since the quantum initiative was launched includes a $4 million research partnership between researchers at Brown and Dartmouth, led by Vesna Mitrović, a professor of physics. The project aims to develop a fundamental understanding of quantum systems in order to better control them for use in quantum technology. In addition to Mitrović, the Brown team includes theorists and professors Dima Feldman and Brad Marston.

Mitrović will lead two other recently awarded quantum grants. One of those is an initial-stage award from NSF’s Quantum Leap Challenge Institutes program, which will help Brown build capacity toward additional Challenge Institute funding. Another grant funds Mitrović work on the exotic quantum states that emerge from spin-orbit entanglement, the interaction between the orbit of an electron around a nucleus and the electron’s spin (its individual magnetic moment).

Xiao’s grant, which is a collaboration between faculty in physics and engineering, aims to create a “magnetic camera” to image the magnetic fields created by quantum materials. The proposal, which was awarded $2 million from NSF, emerged in part from a meeting organized by the office of Jill Pipher, Brown’s vice president for research.

“She invited us to a brown bag lunch where we gave talks about what we do,” Xiao said. “That helped us to form teams that could identify interesting and important problems and work toward solutions.”

Pipher plans to continue looking for ways to bring researchers together to advance quantum science.

“Quantum technology is one of the most exciting and dynamic fields of research today, with the potential to drive huge advances in solving a range of problems in society,” said Pipher, who is also a professor of mathematics. “Brown’s research office is helping faculty across several fields, including engineering, physics and chemistry, to harness their collective expertise, to build robust collaborations and then to pursue and win major funding opportunities.”

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Prof. Vesna Mitrovic – NSF-funded Brown, Dartmouth researchers to explore materials, matter states for quantum technologies

Original article – https://www.brown.edu/news/2019-11-06/quantumawards

Tackling turbulence: Researchers to take new look at an old problem in physics

Victoria Kabakian Uncategorized

Physics professor Brad Marston is part of an international project supported by a $4 million grant from the Simons Foundation to study turbulence, one of the great unsolved problems of classical physics.

A Brown University physicist will be part of an international team of researchers taking a new look at an old problem in physics: turbulence.

Despite the fact that turbulent fluid flows are nearly everywhere, from jet streams in the atmosphere to the currents in the ocean to the wind flowing over an airplane wing, scientists still don’t have a good general theory of turbulence, says Brad Marston, professor of physics at Brown.

“We have some approximate ways of describing it, some empirical rules of thumb,” Marston said. “But if Boeing wants to model the airflow over a wing, the world’s largest supercomputer can’t do that. So there’s a push toward coming up with new ways of looking at the problem.”

Marston is part of a group of physicists and mathematicians looking to use statistical physics — which is used to explain the collective behavior of systems with lots of individual parts — to develop a new theory of turbulence. The team is supported by a $4 million grant from the Simons Foundation, a nonprofit organization that supports research in mathematics and basic science.

In particular, Marston is working with a group that’s trying to see if statistical theories of phase transitions might be applicable to turbulent flows. To do that, the team will study a simple system in which turbulence arises: a long, cylindrical pipe with water flowing through it. The simplicity of the system will enable the researchers to carefully analyze it using both experiments and computer modeling. And it’s a good testing ground for the phase-transition idea, Marston says.

“When you push water through this pipe, it starts off as a nice, regular flow,” Marston says. “But as it picks up speed, there start to be little puffs of turbulence that move along with the regular flow. As the speed picks up more, eventually the whole thing becomes turbulent. What we’re exploring is the idea that there’s a critical point where this flow becomes turbulent, and whether we can understand that transition by borrowing from theories of phase transitions.”

If those phase transitions do apply, Marston says, it might be possible to simplify the equations used to describe the statistics of turbulence, which are notoriously difficult to solve.

“That might make modeling more efficient or allow us to reach problems that we couldn’t before,” Marston said. “It might also lead back to a simpler theory of turbulence or clarify how to develop better theories.”

Marston and colleagues at Brown will handle the computer modeling part of the project with the help of Brown’s Center for Computation and Visualization and develop statistical theories based upon modeling and experiments.

“If we’re successful, we may have simpler theory of turbulence based on phase transitions, or maybe we can show that that picture is too simplistic,” Marston said. “That would be progress too.”

Original article: https://www.brown.edu/news/2019-11-07/turbulence