Ag2Te simultaneously shows high mobility and low thermal conductivity, however the relatively low band gap of 0.2 eV prevents it from achieving high thermoelectric figure of merit, zT, in the high temperature phase. In this study, the band gap of Ag2Te has been increased enabling a zT of unity by forming alloys and composites with PbTe, thereby demonstrating the importance of exploiting potenti...

Cadmium telluride (CdTe) tetrapods are synthesized with varying aspect ratios through multiple injections of the Te precursor, which provides an excellent means of controlling and tailoring the optical properties of the tetrapods. The self-assembly of CdTe tetrapods at the air/water interface is explored using the Langmuir-Blodgett (LB) technique due to potential use in solar cells arising from...

The successful exfoliation of atomically-thin bismuth telluride (Bi2Te3) quintuple layer (QL) attracts tremendous research interest in this strongly anharmonic quasi-two-dimensional material. The thermal transport properties of this material are not well understood, especially the mode-wise properties and when it is coupled with a substrate. In this work, we have performed molecular dynamics si...

A bulk single crystal sample of cadmium telluride (CdTe) was irradiated with a ~3 mJ/cm infrared femtosecond laser and analyzed with time-resolved X-ray diffraction (XRD) performed on an in-air tabletop designed for an extremely short pulsed X-ray source. The integrated intensity of Kα XRD lines from the CdTe (111) plane was decreased by 4%–5% in the time scale of ~200 ps. The changes in integr...

Dead-time losses are well recognized and studied drawbacks in counting and spectroscopic systems. In this work the abilities on dead-time correction of a real-time digital pulse processing (DPP) system for high-rate high-resolution radiation measurements are presented. The DPP system, through a fast and slow analysis of the output waveform from radiation detectors, is able to perform multi-para...

Void defects were demonstrated to form away from the substrate-epifilm interface during the molecular beam epitaxial growth of mercury cadmium telluride on cadmium zinc telluride substrates. These were smaller in size compared to voids which nucleated at the substrate-epifilm interface, which were also observed. Once nucleated, voids usually replicated all the way to the surface even if the flu...

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and γray detection. The high atomic number of the materials (ZCd =48, ZTe=52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg ∼ 1.5 eV) allows us to operate the detector at room temperature. However, a considerable amount of cha...

The accurate determination of the thermoelectric properties of a material becomes increasingly difficult as the temperature rises. However, it is the properties at elevated temperatures that are important if thermoelectric generator efficiency is to be improved. It is shown that the dimensionless figure of merit, ZT, might be expected to rise with temperature for a given material provided that ...

We present performance data for low-noise free-running high-rate photon counting method for space optical communication and ranging. NASA GSFC is testing the performance of two types of novel photon-counting detectors 1) a 2x8 mercury cadmium telluride (HgCdTe) avalanche array made by DRS Inc., and a 2) a commercial 2880-element silicon avalanche photodiode (APD) array. We successfully measured...

V-VI thermoelectric compounds like Bi2Te3-based alloys are well known for room temperature applications like Peltier coolers or thermogenerators. Their anisotropic physical properties and mechanical weakness are a problem for the manufacturing. To overcome the mechanical problem Spark Plasma Sintering (SPS) was used. 2 inch Wafers of polycrystalline bismuth telluride based n-type and p-type the...