Impact of Acoustic and Optical Phonons on the Anisotropic Heat Conduction in Novel C-Based Superlattices.

C-based XC binary materials and their (XC)/(YC) (X, Y ≡ Si, Ge and Sn) superlattices (SLs) have recently gained considerable interest as valuable alternatives to Si for designing and/or exploiting nanostructured electronic devices (NEDs) in the growing high-power application needs. In commercial NEDs, heat dissipation and thermal management have been and still are crucial issues. The concept of phonon engineering is important for manipulating thermal transport in low-dimensional heterostructures to study their lattice dynamical features.

Strain-Dependent Effects on Confinement of Folded Acoustic and Optical Phonons in Short-Period (XC)/(YC) with X,Y (≡Si, Ge, Sn) Superlattices.

Carbon-based novel low-dimensional XC/YC (with X, Y ≡ Si, Ge, and Sn) heterostructures have recently gained considerable scientific and technological interest in the design of electronic devices for energy transport use in extreme environments. Despite many efforts made to understand the structural, electronic, and vibrational properties of XC and XYC alloys, no measurements exist for identifying the phonon characteristics of superlattices (SLs) by employing either an infrared and/or Raman scattering spectroscopy. In this work, we report the results of a systematic study to investigate the lattice dynamics of the ideal (XC)m/(YC)n as well as graded (XC)10-∆/(X0.

Novel Electrodes and Engineered Interfaces for Halide-Semiconductor Radiation Detectors.

A new class of inorganic halide semiconductors are emerging as high-efficiency low-cost candidates for spectroscopic radiation detection. We report on solving one of the major challenges of these halide radiation detectors. At room temperature halide semiconductor detectors polarize under applied electric field, which not only degrades the charge collection efficiency of the detectors, but also promotes chemical reaction of the metal electrodes with the halide ions.

On the relaxation rate distribution of the photoionized DX centers in indium doped Cd(1-x)Mn(x)Te.

It was recently shown that the kinetics of persistent photoconductivity (PPC) build-up in indium doped Cd(1-x)Mn(x)Te are non-exponential and can be described solely by the stretched-exponential function. The non-exponentiality is attributed to the indium related DX centers present in the materials. In order to explain this observation, low temperature photoconductivity build-up was studied for Cd(1-x)Mn(x)Te:In of two different manganese contents.