Events Daily

Thursday, October 20, 2022
      

Dark-Matter Challenges of the Solid State
Piers Coleman, Rutgers University
Event Type: Physics Dept Colloquium
Time: 4:00 PM -
Location: 726 Broadway, 940, CCPP Seminar
Abstract: At the turn of the 20th century, physicists faced an uncanny range of unsolved problems: simple questions, such as why hot objects change color, why matter is hard and why the sun keeps on shining, went unanswered. These problems heralded a new era of quantum physics. One of the truly remarkable lessons of discovery in this heroic era, was the intertwined nature of research: in the lab and in the cosmos, for solving superconductivity really did help answer why the sun keeps on shining, while looking at the stars provided clues as to why matter is hard.

The challenges facing us today, epitomized by our failure to quantize gravity, the mysteries of dark matter, energy and quantum information, challenge physics to its core. I will discuss some less well-known “dark matter challenges of the solid state”, epitomized by the discovery strange metals with linear resistivity and strange insulators and superconductors which appear to exhibit neutral Fermi surfaces. I will argue that laboratory-scale problems of this ilk challenge our fundamental understanding of matter in new and intriguing ways. As part of this discussion, I will discuss my recent research into the interplay of fractionalization[1], whereby quantum excitations break-up into particles with fractional quantum numbers. We have recently discovered an exactly solvable model of a 3D spin liquid with a Fermi surface and Majorana spin excitations. When coupled to electrons, a superconductor forms with a “fractional” charge e, spin ½ order parameter. I will speculate on the possible applications of this new development. [1] PC, Aaditya Panigrahi, Alexei Tsvelik, “ Solvable 3D Kondo Lattice Exhibiting Pair Density Wave, Odd-Frequency Pairing, and Order Fractionalization”, PRL in press (2022)