A. Slobodskyy

Voltage-controlled spin selection in a magnetic resonant tunneling diode.

We have fabricated all II-VI semiconductor resonant tunneling diodes based on the (Zn,Mn,Be)Se material system, containing dilute magnetic material in the quantum well, and studied their current-voltage characteristics. When subjected to an external magnetic field the resulting spin splitting of the levels in the quantum well leads to a splitting of the transmission resonance into two separate peaks. This is interpreted as evidence of tunneling transport through spin polarized levels, and could be the first step towards a voltage controlled spin filter.

Remanent zero field spin splitting of self-assembled quantum dots in a paramagnetic host

A key element in the emergence of a full spintronics technology is the development of voltage controlled spin filters to selectively inject carriers of desired spin into semiconductors. We previously demonstrated a prototype of such a device using a II-VI dilute-magnetic semiconductor quantum well which, however, still required an external magnetic field to generate the level splitting. Recent theory suggests that spin selection may be achievable in II-VI paramagnetic semiconductors without external magnetic field through local carrier mediated ferromagnetic interactions. We present the first experimental observation of such an effect using non-magnetic CdSe self-assembled quantum dots in a paramagnetic (Zn,Be,Mn)Se barrier.

In-depth analysis of the CuIn1−xGaxSe2 film for solar cells, structural and optical characterization

Space-resolved x-ray diffraction measurements of gradient-etched CuIn1−xGaxSe2 (CIGS) solar cells provide information about stress and texture depth profiles in the absorber layer. An important parameter of CIGS layer growth dynamics, the absorber thickness-dependent stress in the molybdenum back contact, is analyzed. Texturing of grains and quality of the polycrystalline absorber layer are correlated with the intentional composition gradients (band gap grading). The band gap gradient is determined by space-resolved photoluminescence measurements and correlated with composition and strain profiles.

Resonant tunneling diode with spin polarized injector

The authors investigate the current-voltage characteristics of a II-VI semiconductor resonant tunneling diode coupled to a diluted magnetic semiconductor injector. As a result of an external magnetic field, a giant Zeeman splitting develops in the injector, which modifies the band structure of the device, strongly affecting the transport properties. They find a large increase in peak amplitude accompanied by a shift of the resonance to higher voltages with increasing fields. They discuss a model which shows that the effect arises from a combination of three-dimensional incident distribution, giant Zeeman spin splitting, and broad resonance linewidth.

Magnetic-field-induced exchange effects between Mn ions and free carriers in ZnSe quantum wells through the intermediate nonmagnetic barrier studied by photoluminescence

Photoluminescence (PL) of the 50 nm

Three-dimensional reciprocal space profile of an individual nanocrystallite inside a thin-film solar cell absorber layer

Zn_{0.9}Be_{0.05}Mn_{0.05}Se

Solution-processed polymer–silver nanowire top electrodes for inverted semi-transparent solar cells

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Spin injection in the nonlinear regime: band bending effects.

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Magnetic resonant tunnelling diodes as voltage-controlled spin selectors

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All II‐VI magnetic resonant tunneling diodes as voltage controlled spin filters

Zn_{0.943}Be_{0.057}Se