北京师范大学郭文安教授报告

理论物理中心学术报告

Date: 2017.06.11 (Sunday) 9:30AM
Place: Rm 323, Physics Building, Sichuan University
Speaker: 郭文安 教授（北京师范大学）

Title: Finite-size scaling in quantum criticality with two length scales [slides]

Abstract:
The theory of “deconfined” quantum critical points describes phase transitions at temperature T=0 outside the standard paradigm, predicting continuous transformations between certain ordered states where conventional theory requires discontinuities. Numerous computer simulations have offered no proof of such transitions, however, instead finding scaling violations which were neither predicted by the new theory nor conform with standard scenarios. In this talk, I will show that this enigma can be resolved by introducing a critical scaling form with two divergent length scales. I will also present simulation results of a quantum magnet with antiferromagnetic and dimerized ground states which confirm the form, proving a continuous transition with deconfined excitations and also explaining anomalous scaling at T>0. Our findings revise prevailing paradigms for quantum criticality.