Spin-depedent transmission of holes through periodically modulated diluted magnetic semiconductor waveguides

TL;DR

This paper investigates how holes with different spins transmit through periodically modulated waveguides with diluted magnetic semiconductor sections, revealing oscillatory behaviors and potential for spin filter applications.

Contribution

It introduces a detailed analysis of spin-dependent hole transmission in periodically modulated DMS waveguides, highlighting new oscillatory phenomena and design strategies for spin filters.

Findings

Transmission oscillates with DMS section width for spin-down holes.

Wide plateaus in polarization achieved with asymmetric stubs.

Periodic gaps in transmission for spin-down holes with varying DMS width.

Abstract

We study spin transport of holes through stubless or stubbed waveguides modulated periodically by diluted magnetic semiconductor (DMS) sections of width b1 . Injected holes of up (down) spin feel a periodically modulated barrier (well) potential in the DMS sections and have different transmission (T) coefficients. T oscillates with b1 for spin-down and decreases fast for spin-up holes while the relative polarization Pr depends nearly periodically on the stub height. Using asymmetric stubs leads to a nearly square-wave pattern in T and to wide plateaus in Pr . T oscillates with the length between the DMS sections. With two DMS sections per unit, T shows periodically wide gaps for spin-down holes when a DMS width is varied. The results can be used to create efficient spin filters.