paper

Superconducting quantum criticality of topological surface states at three loops

arXiv:1605.09423 · doi:10.1103/PhysRevB.94.205106

Abstract

The semimetal-superconductor quantum phase transition on the two-dimensional (2D) surface of a 3D topological insulator is conjectured to exhibit an emergent supersymmetry, based on a renormalization group (RG) analysis at one-loop order in the expansion. We provide additional support for this conjecture by performing a three-loop RG analysis and showing that the supersymmetric fixed point found at this order survives the extrapolation to 2D. We compute critical exponents to order , obtaining the more accurate value for the correlation length exponent and confirming that the fermion and boson anomalous dimensions remain unchanged beyond one loop, as expected from non-renormalization theorems in supersymmetric theories. We further couple the system to a dynamical gauge field, and argue that the transition becomes fluctuation-induced first order. We discuss implications of this result for quantum phase transitions between certain symmetry-preserving correlated surface states of 3D topological insulators.

19 pages, 11 figures; v2: published version [Editors' Suggestion]

References in corpus (10)

Cited by in corpus (55)