Cathodoluminescence study of diluted magnetic semiconductor quantum well/micromagnet hybrid structures

Abstract

Cathodoluminescence (CL) was studied in hybrid structures consisting of a diluted magnetic semiconductor (DMS) Cd1−xMnxTe (x=0.06 and 0.09) quantum well buried 300 Å below the surface on which Fe islands with micrometric dimensions were deposited. The CL at T=10 K collected from areas far away from the Fe island was consistent with the photoluminescence spectra obtained prior to Fe deposition as were the raster scans and spot excited CL spectra taken in nonmagnetized structures close to the Fe islands. After a magnetization at a magnetic field of 3 T, the CL peak related to DMS quantum well (QW) shifts by up to 4 meV to lower energy only when the exciting beam is focused close to edges of an island. The observed shifts are interpreted as due to a fringe field, affecting the DMS QW, of magnetic domains formed in the Fe islands. The experiments prove a feasibility of the concept of usage of the fringe fields to achieve further confinement of excitons in submicron DMS/ferromagnet hybrid structures.

Kramers polarization in strongly correlated carbon nanotube quantum dots

“…26 The influence of the magnetic stray fields on the spin-states in semiconductor materials has been investigated by photoluminescence, 27 spin-flip light scattering, 28 and cathodoluminiscense in semiconductor quantum wells. 29 Our results show that due to the combined action of spin-orbit interaction and stray fields a new type of polarization between time-reversal electronic states is generated. Our goal in this work is to investigate the influence of all three polarizations (spin, orbital, and Kramers) in the formation of the SU(4) Kondo state in a carbon nanotube quantum dot.…”

Light scattering study on hybrid structures of Zn1−x−yCdxMnySe quantum wells with ferromagnetic Co wires

“…Moreover, it is important to develop microstructures in which local magnetic fields can be applied to the DMS quantum structures for realizing spin related or magneto-optical devices, since the DMS is paramagnetic at room temperature. Recently, a hybrid structure of the DMS with a 6 µm square Fe thin film on it has been reported [2]. However, in that isolated Fe pattern, the formation of magnetic domains prevents the uniform field application to the DMS.…”

Optical Properties of a Semimagnetic Quantum Well in a Proximity of a Superconducting Film

“…The idea of placing magnetic structures (like ferromagnetic islands or type I superconductors) in the proximity of a DMS layer and using this layer as a magneto-optical detector of a magnetic field can be found in many papers [2][3][4][5]. In this paper, we consider the influence of a type II superconductor (SC) on optical properties of a DMS quantum well (QW).…”