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We use terahertz time-domain spectroscopy to measure the complex dielectric function of long-wave infrared Hg1-xCdxTe films (x = 0.18, 0.20, 0.22) as a function of temperature in a noncontact manner. Using a Drude–Lorentz model fit to the measured complex transmission function combined with a Kane model description of the band structure, we obtain the temperature-dependent conduction band carrier density, effective mass, scattering time, and carrier mobility for all three Hg1−xCdxTe films. The optical properties of a bare substrate of Cd0.96Zn0.04Te were also measured in the terahertz region. The high quality of the Hg1−xCdxTe films is demonstrated by ultrahigh mobilities exceeding 105 cm2V−1s−1 and ionized donor densities less than 3 × 1015 cm−3 at temperatures below 100 K.

Gastroesophageal reflux disease and temporomandibular joint disorder are common medical conditions with a potential causal relationship. This study aims to investigate the possible causal relationship between GERD and TMD through bidirectional Mendelian randomization analysis.

To investigate the sizing-up effects of microchannel reactors, a 0.6 mm i.d. microchannel reactor along with a 2 mm i.d. tube reactor, a 3 mm i.d. tube reactor, and a 4 mm i.d. tube reactor was assembled, and their micromixing performance was evaluated experimentally with the I–/IO3–parallel competitive reaction system at different Re. The results showed that at low Re, the segregation index XS(used to characterize the micromixing efficiency) of all tube reactors decreased (indicating strengthened micromixing efficiency) noticeably with increasing Re, and the XSof tube reactors with a bigger inner diameter was much larger than that of the reactors with a smaller inner diameter at the same Re. When Rewas bigger than 5584, the XSof all tube reactors with different inner diameters would become almost the same as ∼3.4 × 10–4and remained unchanged with further increasing Re, suggesting a negligible sizing-up effect of the microchannel reactor on the micromixing performance at sufficiently high Re. In addition, Ni–Co–S composites were prepared in the four different tube reactors at the optimal Reof 6700, and the physical and electrochemical properties of the prepared Ni–Co–S composites were almost the same, further demonstrating the negligible sizing-up effects of the microchannel reactor at high Re.

In spite of many attempts to find better material for infrared detectors, HgCdTe still dominates the high performance end of the market. At present, the research in this field is directed towards high pixel density, high yield, reduced cooling and hyperspectral operation. Long lasting issue of availability of high quality, large area substrates for epitaxial growth of HgCdTe seems to be easing recently with development of 4" CdZnTe lattice matching substrates reported recently. The quality of HgCdTe grown on alternative substrates like silicon, GaAs or recently investigated GaSb still falls behind that achievable on CdZnTe due to large lattice mismatch leading to high defect density. Recent effort to scale down the pixel size and pitch resulted in development of diffraction limited high definition focal plane arrays. Implementation of unipolar n-type/barrier/n-type detector structure in HgCdTe material system has been recently proposed and studied intensively. Due to superior transport and optical properties of HgCdTe it is expected that, when optimized, these structures will allow for background limited performance at significantly higher operating temperatures.

In this paper, the effects of thermal annealing (TA) were studied by theoretical calculation and experiment. The calculation was based on the Masafumi's model of dislocation movement, modified with thermal stress and lattice-mismatch in the HgCdTe/CdTe/Si(211) heterostructure. As the calculation indicated, the temperature and holding time of TA had great effect on the dislocation reduction, while less improvement with the epilayer thickness and growth orientation. Upon the result of calculation, the TA and thermal cycle annealing (TCA) experiments were performed under different conditions, which fit the calculation properly. The dislocation reduction of TA was investigated by double crystal X-ray rocking curve (DCRC) and etch pit density (EPD) measurements. The EPD of 10m SW~LW HgCdTe/Si under optimized thermal process could be decreased half order of magnitude, with the lowest EPD at 2×106cm-2, as well as the full width at half maximum (FWHM) of the DCRC to 57.8 arcsec.

In spite of many attempts to find better material for infrared detectors, HgCdTe still dominates the high performance end of the market. At present, the research in this field is directed towards high pixel density, high yield, reduced cooling and hyperspectral operation. Long lasting issue of availability of high quality, large area substrates for epitaxial growth of HgCdTe seems to be easing recently with development of 4” CdZnTe lattice matching substrates reported recently. The quality of HgCdTe grown on alternative substrates like silicon, GaAs or recently investigated GaSb still falls behind that achievable on CdZnTe due to large lattice mismatch leading to high defect density. Recent effort to scale down the pixel size and pitch resulted in development of diffraction limited high definition focal plane arrays. Implementation of unipolar n-type/barrier/n-type detector structure in HgCdTe material system has been recently proposed and studied intensively. Due to superior transport and optical properties of HgCdTe it is expected that, when optimized, these structures will allow for background limited performance at significantly higher operating temperatures.