Time-resolved differential transmission in MOVPE-grown ferromagnetic InMnAs

We present a theoretical platform for modeling the electronic and magneto-optic properties of magnetically doped core-shell nanoparticles that has, as a central prediction, a mechanism by which the g-factors in these nanoparticles can be tuned over a wide range by controlled positioning of magnetic impurities. We illustrate this effect for wide gap Mn-doped CdS-ZnS core-shell particles and point out several unexpected trends that merit extended experimental investigation. Structure-property relations are also discussed. The ability to tune g-factors will make core-shell nanostructures viable candidates for spintronic applications, and the comprehensive modeling approach outlined here will be a powerful tool for predicting their properties as well as for optimizing the design of novel spintronic devices.

show abstract

“…In this case the average spin on a Mn site would be obtained by solving a transcendental equation for S z as described in Ref. 78.…”

Section: Manganese Impurity Hamiltonianmentioning

confidence: 99%

Tuninggfactors of core-shell nanoparticles by controlled positioning of magnetic impurities

2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…The spontaneous magnetization depends on the Mn concentration, x , and the z-component of the average Mn spin, S z . In determining the z-component of Mn spin, we can allow for the system to be either paramagnetic or ferromagnetic, this is described in reference [9,37]. The spin of the Mn ions is calculated using mean-field theory, with < S z > determined from:…”

Section: Theoretical Calculations and Modelingmentioning

confidence: 99%

“…Compared to GaMnAs [5], NGFS have smaller band gaps, larger g-factors and spin-orbit coupling [6,7], and much higher electron and hole mobilities. The narrow gap materials are also more interesting and difficult to treat theoretically since there is strong band-mixing between the conduction and valence bands, unlike GaAs where the conduction and valence bands can be treated separately [8,9].…”

Section: Introductionmentioning

confidence: 99%

High-field magnetic circular dichroism in ferromagnetic InMnSb and InMnAs: Spin-orbit-split hole bands andgfactors

et al. 2015

Self Cite

View full text Add to dashboard Cite

Carrier-induced ferromagnetism in magnetic III-V semiconductors has opened up several opportunities for spintronic device applications as well as for fundamental studies of a material system in which itinerant carriers interact with the localized spins of magnetic impurities. In order to understand the hole mediated ferromagnetism, probing the band structure in these material systems is crucial. Here we present magnetic circular dichroism (MCD) studies on MOVPE grown InMnSb and InMnAs, both with the Curie temperatures above 300 K. The measurements were performed on samples with different Mn contents with the excitation energy tuned from 0.92-1.42 eV and external magnetic fields up to 31 Tesla. The large g-factors in these systems allow us to measure the MCD at relatively high temperatures (190 K). These measurements are compared with MCD calculations based on an 8 band Pidgeon-Brown model which is generalized to include the coupling between the electron/hole and the Mn spin in a ferromagnetic state. Comparison of the observed MCD with the theoretical calculations provides a direct method to probe the band structure including the temperature dependence of the spin-orbit split-off gap and g-factors, and to estimate the sp-d coupling constants.

show abstract

“…[19][20][21][22][23][24][25] . Specifically, picosecond and femtosecond spectroscopy experiments in high magnetic fields have been limited to special magnets and/or facilities within high magnetic field laboratories, 26,27 including the Ultrafast Optics Facility at the National High Magnetic Field Laboratory. This facility has recently developed a new direct current (DC) high field magnet, the Split-Florida Helix, 28 which combines direct optical access via four elliptical window ports with magnetic fields up to 25 T to greatly expand the number of possible spectroscopic experiments utilizing high magnetic fields.…”

Section: Introductionmentioning

confidence: 99%

A table-top, repetitive pulsed magnet for nonlinear and ultrafast spectroscopy in high magnetic fields up to 30 T

Noe

Nojiri

Lee

et al. 2013

Review of Scientific Instruments

View full text Add to dashboard Cite

We have developed a mini-coil pulsed magnet system with direct optical access, ideally suited for nonlinear and ultrafast spectroscopy studies of materials in high magnetic fields up to 30 T. The apparatus consists of a small coil in a liquid nitrogen cryostat coupled with a helium flow cryostat to provide sample temperatures down to below 10 K. Direct optical access to the sample is achieved with the use of easily interchangeable windows separated by a short distance of ∼135 mm on either side of the coupled cryostats with numerical apertures of 0.20 and 0.03 for measurements employing the Faraday geometry. As a demonstration, we performed time-resolved and time-integrated photoluminescence measurements as well as transmission measurements on InGaAs quantum wells.

show abstract

Time-resolved differential transmission in MOVPE-grown ferromagnetic InMnAs

Cited by 14 publications

References 29 publications

Tuninggfactors of core-shell nanoparticles by controlled positioning of magnetic impurities

Tuninggfactors of core-shell nanoparticles by controlled positioning of magnetic impurities

High-field magnetic circular dichroism in ferromagnetic InMnSb and InMnAs: Spin-orbit-split hole bands andgfactors

A table-top, repetitive pulsed magnet for nonlinear and ultrafast spectroscopy in high magnetic fields up to 30 T

Contact Info

Product

Resources

About