We have studied experimentally and theoretically the cross-plane Seebeck coefficient of short period InGaAs/InAlAs superlattices with doping concentrations ranging from 2x10(18) up to 3x10(19) cm(-3). Measurements are performed with integrated thin film heaters in a wide temperature range of 10-300 K. It was interesting to find out that contrary to the behavior in bulk material the Seebeck coef...

Within the envelop-function framework, we developed the finite element method to calculate theminibands in the realist Silicon nanocrystal array. This method clearly reveals the miniband formation and accurately calculates the E–K dispersion relationship. In the simple 1D array, the deduced miniband structure matches well with the analytic Kronig–Penney method. More importantly, it can better s...

Periodic stacking of topologically trivial and non-trivial layers with opposite symmetry the valence conduction bands induces topological interface states that, in strong coupling limit, hybridize both across normal insulator layers. Using band structure engineering, such superlattices can be effectively realized using IV-VI lead tin chalcogenides. This leads to emergent minibands a tunable top...

We report on a broadband GaAs/AlAs superlattice detector for THz radiation; a THz field reduces the current through a superlattice, which is carried by miniband electrons, due to modulation of the Bloch oscillations of the miniband electrons. We studied the detector response, by use of a free electron laser, in a large frequency range ~5–12 THz!. The responsivity showed strong minima at frequen...

A new, exact method for calculating excitonic absorption in superlattices is described. It is used to obtain high resolution spectra showing the saddle point exciton feature near the top of the miniband. The evolution of this feature is followed through a series of structures with increasing miniband width. The Stark ladder of peaks produced by an axial electric field is investigated, and it is...

The luminescence properties of highly strained, Sb-doped Ge/Si multi-layer heterostructures with incorporated Ge quantum dots (QDs) are studied. Calculations of the electronic band structure and luminescence measurements prove the existence of an electron miniband within the columns of the QDs. Miniband formation results in a conversion of the indirect to a quasi-direct excitons takes place. Th...

We present and analyse solutions of a recent derivation of a drift-diffusion model of miniband transport in strongly coupled superlattices. The model is obtained from a single-miniband Boltzmann–Poisson transport equation with a BGK (Bhatnagar–Gross–Krook) collision term by means of a consistent Chapman–Enskog expansion. The reduced drift-diffusion equation is solved numerically and travelling ...

The electronic structure of finite parabolic GaAs/Alx Ga1−xAs superlattices is studied. A detailed analysis of the miniband formation is given and the importance of all system parameters is discussed. The dependence of the equidistant miniband separation on the superlattice size is revealed. A comparison with different theoretical methods and experimental data is presented. The calculations are...

We present theoretically that the cross-plane Seebeck coefficient of InGaAs/ InGaAlAs III–V semiconductor superlattices can be significantly enhanced through miniband transport at low temperatures. The miniband dispersion curves are calculated by self-consistently solving the Schrödinger equation with the periodic potential, and the Poisson equation taking into account the charge transfer betwe...