PIRSA:16110077

Transport in Chern-Simons-Matter Theories

Mahajan, R. (2016). Transport in Chern-Simons-Matter Theories. Perimeter Institute. https://pirsa.org/16110077

Mahajan, Raghu. Transport in Chern-Simons-Matter Theories. Perimeter Institute, Nov. 21, 2016, https://pirsa.org/16110077 

          @misc{ pirsa_PIRSA:16110077,
            doi = {10.48660/16110077},
            url = {https://pirsa.org/16110077},
            author = {Mahajan, Raghu},
            keywords = {Condensed Matter},
            language = {en},
            title = {Transport in Chern-Simons-Matter Theories},
            publisher = {Perimeter Institute},
            year = {2016},
            month = {nov},
            note = {PIRSA:16110077 see, \url{https://pirsa.org}}
          }

Raghu Mahajan Stanford University - Department of Physics

DOI 10.48660/16110077
Collection
Talk Type Scientific Series
Subject

Abstract

The frequency-dependent longitudinal and Hall conductivities — σ_xx and σ_xy — are dimensionless functions of ω/T in 2+1 dimensional CFTs at nonzero temperature. These functions characterize the spectrum of charged excitations of the theory and are basic experimental observables. We compute these conductivities for large N Chern-Simons theory with fermion matter. The computation is exact in the ’t Hooft coupling λ at N = ∞. We describe various physical features of the conductivity, including an explicit relation between the weight of the delta function at ω = 0 in σ_xx and the existence of infinitely many higher spin conserved currents in the theory. We also compute the conductivities perturbatively in Chern-Simons theory with scalar matter and show that the resulting functions of ω/T agree with the strong coupling fermionic result. This provides a new test of the conjectured 3d bosonization duality. In matching the Hall conductivities we resolve an outstanding puzzle by carefully treating an extra anomaly that arises in the regularization scheme used.