Physics Colloquium - Do Metals Exist at T=0? Do Insulators Exist at T>0?

Event Date: 

Tuesday, March 10, 2015 - 4:00pm

Event Location: 

  • Broida 1640

Chetan Nayak, KITP, UCSB


Metals can be unstable at low temperatures to various ordering phenomena such as superconductivity and density waves as well as to localization by impurities. In 1D and 2D materials, these tendencies are especially powerful and, according to conventional wisdom, a normal metal is not possible at T=0; only superconducting and insulating states can occur. By contrast, at T>0, all materials are expected to have non-zero (though possibly very small) conductivity due to thermally-activated processes. In this talk, I will explain why both of these articles of conventional wisdom are wrong: a stable metallic phase can exist at T=0 and a material can be completely insulating at T>0.