Spin interference in silicon one-dimensional rings

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 (1 0 0) surface using the planar diffusion CVD technology. The coherence and phase sensitivity of spin-dependent transport of holes are studied by varying the value of external magnetic field and gate voltage that are perpendicular to the plane of the double-slit ring. Firstly, quantum scatterers connected to two one-dimensional leads and 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 (2e 2/h) feature of hole quantum conductance staircase revealed by the quantum point contact inserted are found to result from the interplay of spontaneous spin polarization and Rashba spin-orbit interaction.