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We report a design and electroluminescence (EL) investigation of a p-i-n resonant tunneling device based on an Al0.4Ga0.6As/GaAs graded-index waveguide heterostructure. The intrinsic region of the structure consists of a quantum well (QW) surrounded by multiple barrier energy filters providing simultaneous resonant occupation of electron and heavy-hole second excited subbands in the QW. Several peaks are observed in the EL spectra, confirming occupation of the excited subbands. The EL efficiency displays a resonant behavior accompanied by an S-shaped negative differential resistance region in the voltage–current characteristic. Current bistability is demonstrated, leading to bistability in the EL and laser generation spectra.

We present photoluminescence excitation (PLE) and picosecond time-resolved photoluminescence (TRPL) results of an aperiodic superlattice (ASL) in static electric fields applied perpendicular to the heterojunction interfaces. The ASL consists of nine GaAs quantum wells separated by Al 0.4 Ga 0.6 As barriers of varying thickness, such that electronic states in individual QWs are in resonance in a finite electric field (∼45 kV cm 1 ). We observed a drastic quenching of the photoluminescence intensity when the field is increased over a critical value, and a triple resonance of the heavy-hole exciton states originally confined in neighboring QWs, confirming the formation of an electron quasi-miniband. The TRPL and PLE spectra also suggest that the Coulomb-interaction-induced redistribution of exciton oscillator strength is strongly field-dependent at the resonant field. The ASL structure is demonstrated to achieve control of both optical and transport properties in desired electric fields. Theoretical calculations emphasis on the electron state resonance and the exciton radiative lifetime are performed to understand the experimental data.

In this paper we present the detailed thermodynamic analysis and experimental study on the MBE growth process of heteroepitaxial InSb layers on strongly lattice-mismatched GaAs(100) and Si(100) substrates. A good qualitative agreement between theoretical and experimental results has been obtained. The influence of growth parameters (Tsub, Sb4In flow ratio) on the structural, electrical, and luminescence characteristics of the layers has been also investigated. The increase of Tsub from 350 to 420°C together with the Sb4In flow ratio reduction result in a mirror-like surface morphology, decrease in X-ray rocking curve FWHM values and dislocation density down to 210 arcsec and 1 × 108 cm−2, respectively, and the disappearance of stacking faults. It also provides a lower unintentional doping level (n ∼ 2.8 × 1016 cm−3) in undoped layers and a higher electron mobility (51000 cm2/V · s at 300 K and 36000 cm2/V · s at 77 K). Using Be as a p-type dopant has been shown to enable to reach readily the Be doping level of InSbGaAs and InSbSi as high as 2 × 1019 cm−3.

This paper reports the effect of growth parameters and buffer structure on the luminescence electrical and structural characteristics of thin (

The photoluminescent properties of quantum dots formed in the deposition of an InSb thin film (1–3 monolayers) on GaAs(100) and GaSb(100) surface are investigated. The results indicate the importance of As-Sb substitution reactions in the formation of quantum dots on a GaAs surface.