Dielectric breakdown via emergent nonequilibrium steady states of the electric-field-driven Mott insulator

Article

关键词: TO-METAL TRANSITION;    QUANTUM RECURRENCE THEOREM;    SUPERLATTICES;    TRANSPORT;    MANGANITE;    SYSTEM;    GASES;    LIGHT;   

DOI  :  10.1103/PhysRevB.89.205126

来源: SCIE

【 摘 要 】

In this work, we explore the possibility of emergent nonequilibrium steady states arising from the electric-field-driven Mott insulator via the Keldysh-Floquet dynamical mean-field theory (DMFT), which can determine the fully interacting, nonequilibrium steady-state Green's functions with the noninteracting counterparts as an input to the DMFT self-consistency loop. Unlike the retarded component, obtaining the lesser Green's function for the noninteracting system presents an important obstacle since the thermalization of the noninteracting system still requires a precise understanding of the dissipation mechanism. A crucial breakthrough in this work is that the noninteracting lesser Green's function can be determined in terms of the Wannier-Stark ladder (WSL) eigenstates, which are thermalized via the standard canonical ensemble according to the Markovian quantum master equation. As a result, it is shown that the intricate interplay between strong correlation and large electric field can generate a sequence of two dielectric breakdowns with the first induced by a coherent reconstruction of the midgap state within the Mott gap and the second by an incoherent tunneling through the biased Hubbard bands. It is predicted that the reconstructed midgap state generates its own emergent WSL structure with a reduced effective electric field. The two dielectric breakdowns are mediated by a reentrant insulating phase, which is characterized by the population inversion, causing instability toward inhomogeneous current density states at weak electron-impurity scattering.

【 授权许可】

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