Interference as a Probe of Spin Incoherence in Strongly Interacting Quantum Wires

TL;DR

This paper proposes using interference experiments to identify the spin-incoherent regime in strongly interacting quantum wires, highlighting magnetic field dependence and anomalous voltage scaling as key signatures.

Contribution

It introduces a method to detect spin-incoherence in quantum wires through interference contrast analysis, providing a new experimental approach.

Findings

Interference contrast strongly depends on magnetic field in the spin-incoherent regime.

Interference contrast exhibits anomalous voltage scaling with a temperature and magnetic field dependent exponent.

The method distinguishes spin-incoherent from spin-polarized regimes, aiding interpretation of conductance anomalies.

Abstract

We show that interference experiments can be used to identify the spin-incoherent regime of strongly interacting one-dimensional conductors. Two qualitative signatures of spin-incoherence are found: a strong magnetic field dependence of the interference contrast and an anomalous scaling of the interference contrast with the applied voltage, with a temperature and magnetic field dependent scaling exponent. The experiments distinguish the spin-incoherent from the spin-polarized regime, and so may be useful in deciding between alternative explanations proposed for the anomalous conductance quantization observed in quantum point contacts and quantum wires at low density.