Dilute magnetic semiconductor quantum-well structures for magnetic field tunable far-infrared/terahertz absorption

Magnetic field tunable terahertz quantum well infrared photodetector

Quasi two-dimensional carriers in dilute-magnetic-semiconductor quantum wells under in-plane magnetic field

Due to the competition between spatial and magnetic confinement, the density of states of a quasi two-dimensional system deviates from the ideal step-like form both quantitatively and qualitatively. We study how this affects the spin-subband populations and the spin-polarization as functions of the temperature, T , and the in-plane magnetic field, B, for narrow to wide dilute-magnetic-semicondu...

Magneto-optical studies of dilute nitrides and II-VI diluted magnetic semiconductor quantum structures

Magnetic Semiconductor Quantum Dots

Cdo.5Mno.5S diluted magnetic semiconductor (DMS) quantum dots (QDs) of crystallite size ranging from 24 A to the bulk have been chemically synthesized using an aqueous solution precipitation method and thermal annealing. Subsequent characterization indicates that the "as prepared" material is of the cubic zinc blende structure which evolves with increasing size to the bulk hexagonal wurtzite st...

Absorption Modulation in Field Effect Quantum Well Structures

We present investigations of modulation of the absorption in InGaAs/In& modulation doped single quantum well structures used as conducting channel in field effect transistors. The electron concentration can be tuned continuously from N-0 to N=: 6.5~10" cm " using the gate voltage. The effects give in situ information on the 2D-electron gas. Furthermore the total quenching of the absorption seen...