Events Daily

Thursday, October 19, 2023

A View from the CERN Council (brown bag talk and discussion)
Eliezer Rabinovici, Hebrew University of Jerusalem
A Flag Icon Event Type: Informal HEP Talk
Time: 12:15 PM - 1:15 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: CERN Council is the body that decides on the scientific and financial policy of CERN. I will review the governance structure at CERN and describe the process of deciding on CERN's future plans including the status of the Future Circular Collider Feasibility Study.

Beyond BCS: An Exact Model for Superconductivity and Mottness
Phillip Phillips, University of Illinois Urbana-Champaign
Event Type: Physics Dept Colloquium
Time: 4:00 PM - 5:30 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: The Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity described all superconductors until the 1986 discovery of the high-temperature counterpart in the cuprate ceramic materials. This discovery has challenged conventional wisdom as these materials are well known to violate the basic tenets of the Landau Fermi liquid theory of metals, crucial to the BCS solution. Precisely what should be used to replace Landau's theory remains an open question. The natural question arises: What is the simplest model for a non-Fermi liquid that yields tractable results. Our work builds[1] on an overlooked symmetry that is broken in the normal state of generic models for the cuprates and hence serves as a fixed point. The fixed point is quadratic and the only relevant perturbation is in the Cooper channel. However, the resultant superconducting state differs drastically[3] from that of the standard BCS theory. For example the famous Hebel-Slichter peak is absent and the elementary excitations are no longer linear combinations of particles and holes but rather are superpositions of composite excitations. Our analysis here points a way forward in computing the superconducting properties of strongly correlated electron matter. [1] E. Huang, G. La Nave, P. Phillips, Nature Physics volume 18, pages511?516 (2022) [2] PWP, L. Yeo, E. Huang, Nature Physics, 16, 1175-1180 (2020). [3]J. Zhao, L. Yeo, E. Huang, PWP, Phys. Rev. B 105, 184509 ? Published 12 May 2022