Pronounced Purcell enhancement of spontaneous emission in CdTe/ZnTe quantum dots embedded in micropillar cavities Appl. Phys. Lett. 101, 132105 (2012) Effects of Co content on the structural, luminescence, and ferromagnetic properties of Zn1−xCoxSy films J. Appl. Phys. 112, 063712 (2012) Leaky mode analysis of luminescent thin films: The case of ZnO on sapphire J. Appl. Phys. 112, 063112 (2012) Observation of In-related collective spontaneous emission (superfluorescence) in Cd0.8Zn0.2Te:In crystal Appl. Phys. Lett. 101, 091115 (2012) Emission bands of nitrogen-implantation induced luminescent centers in ZnO crystals: Experiment and theory Temperature (11-250 K) and excitation power (5-480 mW) dependent infrared photoluminescence (PL) measurements are conducted on a HgTe=Hg 0:05 Cd 0:95 Te superlattice (SL) sample in a spectral range of 5-18 lm with adequate spectral resolution and signal-to-noise ratio. Three PL components are identified from the evolution of the PL lineshape with temperature although the full-width at half-maximum (FWHM) of the whole PL signal is only about 7 meV at 11 K, for which different changes of the energy, FWHM, and integral intensity are evidenced. The mechanisms are clarified that the medium-energy component is due to electron-heavy hole intersubband transition, while the low-energy (LE) component correlates to localized states and the high-energy (HE) one may originate in interfacial inhomogeneous chemical intermixing and Brillouin-zone boundary effects. The LE and HE component-related effects are responsible for the PL quality of the SL at the temperatures well below and above 77 K, respectively. V C 2012 American Institute of Physics. [http://dx.

Research into P-type doping of HgCdTe with arsenic has concentrated on the use of a conventional effusion cell and optimisation of growth conditions to achieve an increase in incorporation efficiency. This study investigates the use of a cracker cell, which is now the preferred method of doping HgCdTe due to its higher arsenic incorporation efficiency under optimum growth conditions. A detailed investigation of a number of arsenic doped HgCdTe layers grown on CdZnTe substrates by Molecular Beam Epitaxy (MBE) using a cracker cell as a source of arsenic is presented. Growth parameters influencing the amount of arsenic incorporated, such as the cracker-cell bulk temperature and substrate temperature, were investigated. Arsenic depth profiles were obtained via detailed Secondary Ion Mass Spectrometry (SIMS) where all major constituents in the epilayers were analysed. Magneto-transport Hall measurements were performed on as-grown material and those that underwent high temperature anneals typical for arsenic activation. Using the Quantitative Mobility Spectrum Analysis (QMSA) technique, contribution to total conductivity arising by various carriers present in the samples have been separated. As-grown samples were found to exhibit n-type behavior consistent with arsenic incorporating on cation sublattice, while samples that underwent high temperature annealing show partial activation of arsenic with electron compensation.

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In order to evaluate the effectiveness of CdTe surface passivating layers, HgCdTe photoconductors with and without CdTe sidewall passivation were fabricated. As expected, photoconductors with CdTe sidewall passivation demonstrated significantly higher responsivity in comparison with those without sidewall passivation, indicating the effectiveness of molecular-beam epitaxially (MBE)-grown CdTe as a passivation layer in reducing surface recombination velocity. Characterization of the responsivity differences between photoconductors with and without sidewall CdTe passivation offers a potential method for measuring the interface/surface recombination velocity. This has been demonstrated in this paper by extracting the value of the surface recombination velocity using the Synopsys Sentaurus commercial modeling package to fit experimental responsivity data for fully and partially passivated devices.

Arsenic incorporation in HgTe/ Hg 0.05 Cd 0.95 Te superlattices grown by molecular beam epitaxy ͑MBE͒ is reported. The incorporation was carried out by a ␦-doping approach where arsenic was incorporated during MBE growth as acceptors. The superlattices were characterized via high resolution x-ray diffraction, Fourier transform infrared spectroscopy, secondary ion mass spectrometry, and magnetotransport Hall measurements coupled with the quantitative mobility spectrum analysis algorithm.

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HgCdTe is the preferred semiconductor for fabrication of high-performance infrared (IR) detectors. This material also typically contains multiple carrier species for charge transport, which makes characterisation of the mobility and concentration of each species particularly difficult. Accurate carrier transport characterisation can be achieved by quantitative mobility spectrum analysis of variable-magneticfield Hall and resistivity data, but this imposes certain conditions concerning sample uniformity and homogeneity. Laser beam induced current (LBIC) is a non-destructive characterisation technique that can be used to qualitatively investigate the electronic properties of HgCdTe samples, specifically including electrically-active defects and p-n junctions. Non-uniformity in the LBIC profiles can also be related to ill-conditioned Hall and resistivity data.

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