Coherent vs incoherent transport in holographic strange insulators

Journal of High Energy Physics

Alexander Krikun¹  Tomas Andrade² 

[1] 0000 0001 2312 1970, grid.5132.5, Instituut-Lorentz for Theoretical Physics, ΔITP, Leiden University, Niels Bohrweg 2, 2333CA, Leiden, The Netherlands;0000 0004 1937 0247, grid.5841.8, Departament de Física Quàntica i Astrofísica, Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, E-08028, Barcelona, Spain;

关键词: Holography and condensed matter physics (AdS/CMT);    Space-Time Symmetries;    Spontaneous Symmetry Breaking;   

DOI  :  10.1007/JHEP05(2019)119

来源: publisher

【 摘 要 】

Holographic strange metals are known to have a power law resistivity rising with temperature, which is reminiscent of the strange metal phases in condensed matter systems. In some holographic models, however, the exponent of the power law in the resistivity can be negative. In this case one encounters phases with diverging resistivity at zero temperature: holographic strange insulators.These states arise as a result of translational symmetry breaking in the system, which can either be strong explicit and relevant in the IR, or spontaneous, but pinned by a small explicit source. In some regards, one can associate these two classes to the normal band insulators due to the strong ionic potential, and Mott insulator due to the commensurate lock in of the charge density wave.We study different features of these classes on the explicit example of a holographic helical model with homogeneous Bianchy VII type translational symmetry breaking, and uncover the main mechanisms underlying transport in these two cases. We find that while transport in the explicit relevant case is governed by the incoherent conductivity, in the pinned spontaneous case the leading contribution comes from the coherent part.

【 授权许可】

Unknown