Conductance of a quantum point contact in the presence of spin-orbit interaction

TL;DR

This paper develops a recursive Green's function method to analyze how spin-orbit interaction affects conductance in quantum point contacts, revealing oscillations caused by spin-orbit coupling but not explaining the 0.7 conductance anomaly.

Contribution

A new recursive Green's function technique is introduced to study spin-dependent conductance in mesoscopic structures with spin-orbit interaction.

Findings

Oscillations in conductance are induced by spin-orbit interaction.

Oscillations may result from multiple reflections due to spin-orbit coupling.

The 0.7 conductance structure is not caused by spin-orbit interaction.

Abstract

A recursive Green's function technique is developed to calculate the spin-dependent conductance in mesoscopic structures. Using this technique, we study the spin-dependent electronic transport of quantum point contacts in the presence of the Rashba spin-orbit interaction. We observed that some oscillations in the `quantized' conductance are induced by the spin-orbit interaction, and indicated that the oscillations may stem from the spin-orbit coupling associated multiple reflections. It is also indicated that the 0.7 structure of the conductance observed in mesoscopic experiments would not stem from the spin-orbit interaction.