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Strain-balanced type-II InAs/InAs1-xSbx superlattices with various compositions (x = 0.22, 0.23, 0.37) and different layer thicknesses (tInAs = 7 nm, tInAsSb = 3.3, 2.3, 2.0 nm, respectively) have been grown by metalorganic chemical vapor deposition on GaSb substrates. X-ray diffraction revealed narrow satellite peaks (full-width-half-maximum of <100 arc sec), indicative of uniform superlattice periodicity and excellent crystallinity, which was also corroborated by cross-sectional transmission electron microscopy observations. Despite relaxation, low-temperature photoluminescence measurements showed peaks at 6.7 μm and 5.8 μm, while photoconductance results showed strong spectral response up to 200 K, when the photoresponse onset was 8.6 μm. [ABSTRACT FROM AUTHOR]

By employing a containerless high-temperature high-vacuum electrostatic levitation technique, the thermophysical properties, including the ratio between the specific heat capacity and the hemispherical total emissivity, the specific volume, and the viscosity, of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass (BMG)-forming liquids have been measured. Compared with Cu50Zr50, the improved glass-forming ability of (Cu50Zr50)95Al5 can be attributed to its dense liquid structure and its high value of viscosity. Additionally, the relationship between the viscosity of various BMG forming liquids at the melting temperature and the elastic properties of the corresponding glasses at room temperature will be compared. [ABSTRACT FROM AUTHOR]

The thermophysical properties, including the specific volume V, the surface tension σ, and the viscosity η, of a Cu46Zr42Al7Y5 bulk metallic glass in the molten state were investigated using a containerless high-temperature high-vacuum electrostatic levitation technique. The viscosity measurements indicate that the Cu46Zr42Al7Y5 alloy exhibits an intermediate fragility with the fragility index m=49. [ABSTRACT FROM AUTHOR]

A nanocontact structure of invar alloy is fabricated by using electron beam lithography and lift-off technique. The current-voltage (I-V) characteristic is measured under various temperatures from 10 to 300 K. We find that the I-V curves are nonlinear and asymmetric, and the resistance change increases when the temperature decreases down to 50 K. We attribute this effect to spin electron scattering by a domain wall trapped in the nanocontact. We also show that the anomaly is not observed in Cu nanocontacts. There is almost no resistance change in a Cu nanocontact with a change in the bias voltage. [ABSTRACT FROM AUTHOR]