Spin interference in silicon one-dimensional rings

TL;DR

This paper demonstrates the spin transistor effect in silicon one-dimensional rings, showing how Rashba spin-orbit interaction influences spin-dependent transport and conductance oscillations in a quantum well system.

Contribution

It presents the first experimental observation of spin interference effects caused by Rashba interaction in silicon quantum rings with detailed analysis of phase and amplitude sensitivities.

Findings

Rashba gate controls spin-dependent conductance oscillations.

Quantum point contact affects the phase of Aharonov-Bohm and Aharonov-Casher oscillations.

The 0.7 conductance feature arises from spin polarization and spin-orbit interaction.

Abstract

We present the first findings of the spin transistor effect caused by the Rashba gate-controlled ring embedded in the p-type self-assembled silicon quantum well that is prepared on the Si (100) surface. The coherence and phase sensitivity of the spin-dependent transport of holes are studied by varying the value of the external magnetic field and the gate voltage that are perpendicular to the plane of the double-slit ring. Firstly, the quantum scatterers connected to two one-dimensional leads and the quantum point contact inserted in the one of the arms of the double-slit ring are shown to define the amplitude and the phase of the Aharonov-Bohm and the Aharonov-Casher conductance oscillations. Secondly, the amplitude and phase sensitivity of the 0.7 feature of the hole quantum conductance staircase revealed by the quantum point contact inserted are found to result from the interplay of the spontaneous spin polarization and the Rashba spin-orbit interaction.