Related papers: THz intersubband electroluminescence from n-type G…

: n-type Ge/SiGe asymmetric-coupled quantum wells represent the building block of a variety of nanoscale quantum devices, including recently proposed designs for a silicon-based THz quantum cascade laser. In this paper, we combine…

Although most work toward the realization of group IV quantum cascade lasers (QCLs) has focused on valence-band transitions, there are many desirable properties associated with the conduction band. We show that the commonly cited…

For the first time, electroluminescence detected in the middle and far infrared ranges from silicon carbide nanostructures on silicon, obtained in the framework of the Hall geometry. Silicon carbide on silicon was grown by the method of…

Silicon-based quantum cascade lasers (QCLs) offer the prospect of integrating coherent THz radiation sources with silicon microelectronics. Theoretical studies have proposed a variety of n-type SiGe-based heterostructures as design…

InGaAs/GaAsBi/InGaAs quantum wells (QWs) were grown on GaAs substrates by gas source molecular beam epitaxy for realizing the type II band-edge line-up. Both type I and type II transitions were observed in the Bi containing W QWs and the…

In this paper we investigate the structural and optical properties of few strain-unbalanced multiple Ge/GeSi quantum wells pseudomorphically grown on GeSi reverse-graded substrates. The obtained high epitaxial quality demonstrates that…

We have fabricated a device which includes two lateral p-n junctions on an n-type GaAs/Al$_{0.33}$Ga$_{0.67}$As heterostructure. A section of the n-type material has been converted to p-type by removing dopants and applying a voltage to a…

Terahertz quantum cascade lasers (THz QCLs) are chip-scale semiconductor lasers operating in the frequency range between 1-6 THz, useful as compact sources for spectroscopy, communications, and non-destructive imaging and testing. Here, we…

We report on a GaN/AlGaN quantum cascade detector operating in the terahertz spectral range. The device was grown by metal organic chemical vapor deposition on a c-sapphire substrate and relies on polar GaN/AlGaN step quantum wells. The…

We report the observation of transverse electric polarized electroluminescence from InAs/AlInAs quantum dash quantum cascade structures up to room temperature. The emission is attributed to the electric field confined along the shortest…

Silicon-based terahertz quantum cascade lasers (QCLs) offer potential advantages over existing III-V devices. Although coherent electron transport effects are known to be important in QCLs, they have never been considered in Si-based device…

Motivated by theoretical predictions that spatially complex concentration modulations of Si and Ge can increase the valley splitting in quantum wells, we grow and characterize Si/SiGe heterostructures with a thin, pure Ge layer at the top…

We explore the midinfrared absorption of strain-compensated p-Si0.2Ge0.8/Si quantum wells for various well thicknesses and temperatures. Owing to the large band offset due to the large bi-axial strain contrast between the wells and…

Terahertz sources based on intra-cavity difference-frequency generation in mid-infrared quantum cascade lasers (THz DFG-QCLs) have recently emerged as the first monolithic electrically-pumped semiconductor sources capable of operating at…

In this Letter, we report the observation of electroluminescence (EL) at around 866 nm from n-i-n unipolar (electron-transporting) III-V GaAs nanoLEDs. The devices consist of nanopillars with top diameter of 166 nm, arranged in a 10x10…

n-type Ge/SiGe terahertz quantum cascade laser are investigated using non-equilibrium Green's functions calculations. We compare the temperature dependence of the terahertz gain properties with an equivalent GaAs/AlGaAs QCL design. In the…

In a recent Letter [Appl. Phys. Lett. 82, 1015 (2003)], Williams et al. reported the development of a terahertz quantum cascade laser operating at 3.4 THz or 14.2 meV. We have calculated and analyzed the gain spectra of the quantum cascade…

We demonstrate THz intersubband absorption (15.6-26.1 meV) in m-plane AlGaN/GaN quantum wells. We find a trend of decreasing peak energy with increasing quantum well width, in agreement with theoretical expectations. However, a blue-shift…

In spite of a large quantity of papers devoted to the mangetoluminescence from CdTe/(Cd,Mg)Te, quantum wells there have been no attempts to analyze it on the basis of the band-structure calculations. This has been proposed in the present…

Intervalley mixing between conduction-band states in low-dimensional Si/SiGe heterostructures induces splitting between nominally degenerate energy levels. The symmetric double-valley effective mass approximation and the empirical…