Physical Society Colloquium

Quantum critical metals and their instabilities

Shamit Kachru

Department of Physics
Stanford University

The problem of understanding quantum critical metals &mdash theories of gapless scalars interacting with a Fermi surface &mdash is arguably at the heart of intriguing physics seen in many materials, including the heavy fermions and the cuprates. Nevertheless, it remains poorly understood. In this colloquium, I will describe in simple language a quantum field theory approach to this class of problems. Results include new intermediate scaling regimes with interesting properties (including a non-Fermi liquid with vanishing Fermi velocity), and enhanced pairing leading to high-scale superconducting (and other) instabilities of the Fermi surface.