Impurity effect on hysteric magnetoconductance: holographic approach

Abstract

In this paper we study a hysteric phase transition from weak localization phase to hysteric magnetoconductance phase using gauge/gravity duality. This hysteric phase is triggered by a spontaneous magnetization related to ℤ2 symmetry and time reversal symmetry in a 2+1 dimensional system with momentum relaxation. We derive thermoelectric conductivity formulas describing non-hysteric and hysteric phases. At low temperatures, this magnetoconductance shows similar phase transitions of topological insulator surface states. We also obtain hysteresis curves of Seebeck coefficient and Nernst signal. It turns out that our impurity parameter changes magnetic properties of the dual system. This is justified by showing increasing susceptibility and the spontaneous magnetization with increasing impurity parameter.

Impurity-driven metal-insulator transitions in holography

“…Therefore, the momentum relaxation parameter can enhance scalar condensation. We observed similar phenomena in the different model [32] in which the momentum relaxation parameter similarly lowers the temperature.…”

“…This method has been applied to various extensions, e.g. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][44][45][46].…”