Ferromagnetic/DMS hybrid structures: one- and zero-dimensional magnetic traps for quasiparticles

TL;DR

This paper explores how ferromagnetic islands on semiconductor quantum wells can create one- and zero-dimensional magnetic traps for quasiparticles with spin, analyzing different shapes and their effects on localization and absorption spectra.

Contribution

It introduces a method to use ferromagnetic micro-structures to generate spin-dependent traps in semiconductors, detailing the effects of shape on trapping dimensions and spectral properties.

Findings

Cylindrical micro-disks can localize spins in three dimensions.

Rectangular micro-magnets create traps allowing free propagation in one direction.

Predicted absorption spectra differ based on magnet shape.

Abstract

We investigated possibility of using local magnetic field originating from ferromagnetic island deposited on the top of semiconductor quantum well to produce zero- and one-dimensional traps for quasi-particles with spin. In particular we considered two shapes of experimentally made magnets - cylindrical and rectangular. In the case of ferromagnetic micro-disk the trap can localize spin in three dimensions, contrary to the rectangular micro-magnet which creates a trap that allows free propagation in one direction. We present in detail prediction for absorption spectrum around the main absorption edge in both type of micro-magnets.