Description:

Title: Quantum Criticality

Speaker: Sudip Chakravarty, UCLA

Abstract: Continuous phase transitions and the associated critical points in interacting systems have fascinated scientists for centuries. These phase transitions are typically tuned by temperature, and at the critical point there are fluctuations on all length scales signifying scale invariance and, in low dimensions, conformal invariance as well. After the pioneering work by John Hertz, condensed matter physicists have been focusing on quantum critical points that are driven purely by quantum fluctuations in the ground states. Recently there has been an explosion of citations of quantum critical points in many condensed matter systems, including high temperature superconductors. The purpose of the talk is to provide an overview of this subject and to point out the relevance to experiments in condensed matter systems, necessarily carried out at finite temperatures. If time permits, I will discuss the non-analyticity of von Neumann entropy as a criterion of criticality at the interface of two distinct ground states of matter. 

Host: Bill Halperin

Speaker Schedule

Keywords: Physics, Astronomy, colloquium