New algorithm could help find new physics

Inverse method takes wave functions and solves for Hamiltonians

Author: Siv Schwink
Published on 8/1/2018

Yuxuan Wang and Eduardo Fradkin in Physical Review B, an editor's suggestion: 'Pair density waves in superconducting vortex halos'

We analyze the interplay between a d-wave uniform superconducting and a pair-density-wave (PDW) order parameter in the neighborhood of a vortex. We develop a phenomenological nonlinear sigma model, solve the saddle-point equation for the order-parameter configuration, and compute the resulting local density of states in the vortex halo. The intertwining of the two superconducting orders leads to a charge density modulation with the same periodicity as the PDW, which is twice the period of the charge density wave that arises as a second harmonic of the PDW itself. We discuss key features of the charge density modulation that can be directly compared with recent results from scanning tunneling microscopy and speculate on the role PDW order may play in the global phase diagram of the hole-doped cuprates.
Published on 5/16/2018

A virus-bacteria coevolutionary 'arms race' solves the diversity paradox by 'Killing the Winner'

U of I Swanlund Professor of Physics Nigel Goldenfeld (left) works with colleague Chi Xue (right) at the Carl R. Woese Institute for Genomic Biology. Photo credit: University of Illinois at Urbana-Champaign.
Author: Siv Schwink
Published on 3/15/2018

Researchers demonstrate existence of new form of electronic matter

Researchers Kitt Peterson, Taylor Hughes, Wladimir Benalcazar and Gaurav Bahl are the first to demonstrate a new phase of matter called quadrupole topological insulators that was recently predicted using theoretical physics.
Author: Lois Yoksoulian for the Illinois News Bureau
Published on 3/15/2018

New understanding of superconductor's 'normal' state may open the way to solving longstanding puzzle

Since the discovery two decades ago of the unconventional topological superconductor Sr2RuO4, scientists have extensively investigated its properties at temperatures below its 1 K critical temperature (Tc), at which a phase transition from a metal to a superconducting state occurs. Now experiments done at the University of Illinois at Urbana-Champaign in the Madhavan and Abbamonte laboratories, in collaboration with researchers at six institutions in the U.S., Canada, United Kingdom, and Japan, have shed new light on the electronic properties of this material at temperatures 4 K above Tc. The team’s findings may elucidate yet-unresolved questions about Sr2RuO4’s emergent properties in the superconducting state.
Author: Siv Schwink
Published on 5/25/2017

Fradkin interviewed by Scientific American: "Bagels, Pretzels and the Nobel Prize in Physics"

The other half of the Nobel prize, awarded for “topological phase transitions,” also unites topology and physics, but “topology enters in a somewhat different way,” says Eduardo Fradkin, a physicist at the University of Illinois Urbana-Champaign.  Relevant here is the fact that topological properties often cannot be determined locally. An ant sitting on a pastry can’t tell by looking around whether the perch is a bun, bagel, or pretzel.
Author: Evelyn Lamb
Published on 10/13/2016

Interdisciplinary sound-wave study holds promise for new technologies

Physics professor Taylor Hughes and mechanical science and engineering professor Gaurav Bahl of the University of Illinois at Urbana-Champaign are part of an interdisciplinary team that will study non-reversible sound wave propagation over the next four years, with a range of promising potential applications.
Author: Siv Schwink
Published on 8/17/2016