Novel metals and insulators from holography

Abstract

Using simple holographic models in D = 4 spacetime dimensions we construct black hole solutions dual to d = 3 CFTs at finite charge density with a Q-lattice deformation. At zero temperature we find new ground state solutions, associated with broken translation invariance in either one or both spatial directions, which exhibit insulating or metallic behaviour depending on the parameters of the holographic theory. For low temperatures and small frequencies, the real part of the optical conductivity exhibits a power-law behaviour. We also obtain an expression for the the DC conductivity at finite temperature in terms of horizon data of the black hole solutions.

Magnetotransport from the fluid/gravity correspondence

“…9 The time-dependent term proportional to λ is also not present in their model. 10 With λ given by (2.23) this expression agrees with the momentum relaxation rate for this model derived in [19].…”

“…By finding ways to incorporate momentum relaxation into these models [1][2][3][4][5][6][7] rapid progress has been made in understanding their DC [8][9][10][11][12][13][14], and low-frequency [15][16][17][18][19] response coefficients.…”

“…Perhaps the most interesting aspects of these results are that holography provides, beyond leading order in the strength of momentum relaxation, a class of non-Drude models of transport (see for instance [10,11,[19][20][21][22]). Such models are likely to be necessary to describe the experimental measurements on strange metals [23][24][25].…”

Momentum relaxation from the fluid/gravity correspondence

“…In particular, for a large class of theories it is now possible to obtain analytic expressions for all the DC conductivities in terms of horizon data [9,10,[14][15][16][17][18]. More recently, the low frequency AC conductivity has been calculated in a simple example by exploiting a clever decoupling of the bulk currents [19].…”

Geometric polarization of plasmas and Love numbers of AdS black branes

“…The constant b in (A.2) is arbitrary and reflects a renormalization scheme dependence. 7 This ambiguity could be fixed by e.g.,…”