Non-equilibrium transport at a dissipative quantum phase transition

TL;DR

This paper investigates non-equilibrium transport phenomena near a quantum phase transition in a dissipative resonant level model, revealing how conductance behavior changes from equilibrium to finite bias voltage conditions.

Contribution

It introduces a rigorous mapping and applies a frequency-dependent renormalization group method to analyze non-equilibrium current in a quantum phase transition setting.

Findings

Conductance matches equilibrium form as bias voltage approaches zero.

Distinct non-equilibrium conductance profile observed at finite bias.

Method provides a controlled approach to study non-equilibrium transport in dissipative quantum systems.

Abstract

We pioneerly investigate the non-equilibrium transport near a quantum phase transition in a generic and relatively simple case model, the dissipative resonant level model, that has many ramifications in nanosystems. We formulate a rigorous mapping and apply a controlled frequency-dependent renormalization group approach to compute the non-equilibrium current in the presence of a finite bias voltage V. For V -> 0, we find that the conductance has its well-known equilibrium form, while it displays a distinct non-equilibrium profile at finite voltage.