Bilocal quantum criticality

Abstract

We consider 2+1 dimensional conformal gauge theories coupled to additional degrees of freedom which induce a spatially local but long-range in time $1/(\tau -{\tau }^{\prime }{)}^2$ interaction between gauge-neutral local operators. Such theories have been argued to describe the hole-doped cuprates near optimal doping. We focus on a SU(2) gauge theory with $N_h$ flavors of adjoint Higgs fields undergoing a quantum transition between Higgs and confining phases: the $1/(\tau -{\tau }^{\prime }{)}^2$ interaction arises from a spectator large Fermi surface of electrons. The large $N_h$ expansion leads to an effective action containing fields which are bilocal in time but local in space. We find a strongly-coupled fixed point at order $1/N_h$, with dynamic critical exponent $z>1$. We show that the entropy preserves hyperscaling, but nevertheless leads to a linear in temperature specific heat with a co-efficient which has a finite enhancement near the quantum critical point.

30 pages, 4 figures

References in corpus (4)

• Phase competition in trisected superconducting dome
• Destruction of Neel order in the cuprates by electron-doping
• Strongly coupled quantum criticality with a Fermi surface in two dimensions: fractionalization of spin and charge collective modes
• Stripe melting and quantum criticality in correlated metals