This study addresses the relationship between thermal microfronts and coherent vortex structures in homogeneous turbulence. The turbulence is created by mean shear in a weakly stratified flow. The data set is generated by direct numerical simulation providing highly resolved instantaneous three‐dimensional fields of fluctuating velocity and temperature (1603 data points...
CuCr₁₋ₓMgₓO₂, a wide band gap semiconductor with the delafossite structure, has been synthesized
in bulk and thin-film form. Bulk undoped CuCrO₂ is almost black and has moderate conductivity
with p-type carriers. Upon doping with 5% Mg, the conductivity increases by a factor of 1000. In
films, the best p-type conductivity...
Transparent p – i – n heterojunction diodes are fabricated using heavily doped, p-type CuYO₂ and
semi-insulating i-ZnO thin films deposited onto a glass substrate coated with n-type indium tin
oxide. Rectification is observed, with a ratio of forward-to-reverse current as high as 60 in the range
−4–4 V. The...
p-type conducting films of α- BaCu₂S₂ have been deposited onto glass and KBr substrates, yielding a conductivity of 17 S/cm and a Hall mobility of 3.5 cm²/Vs. For a 430-nm-thick film, the optical transparency approaches 90% in the visible portion of the spectrum at 650 nm, and a transparency of...
We demonstrate a technique for terahertz pulse shaping via optical rectification in the pre-engineered domain structure of poled lithium niobate crystals. The terahertz wave forms coincide with the crystal domain structures. The one-dimensional nonlinear wave equation simulates the experimental results with a good qualitative agreement.
Highly transparent ZnO-based thin-film transistors (TFTs) are fabricated with optical transmission (including substrate) of ~75% in the visible portion of the electromagnetic spectrum. Current–voltage measurements indicate n-channel, enhancement-mode TFT operation with excellent drain current saturation and a drain current on-to-off ratio of ~10⁷. Threshold voltages and channel mobilities of devices...
BaCuQF (Q=S,Se) materials, candidate transparent p-type conductors, were prepared by solid-state reaction, and their bulk electrical and optical properties were evaluated. The room-temperature Seebeck coefficient and electrical conductivity of undoped BaCuQF pellets were +56 μV/K and 0.088 S/cm, respectively, for the sulfide fluoride, and +32 μV/K and 0.061 S/cm, respectively,...
Transport and structural properties of Mg-doped and O-intercalated sintered powders and
polycrystalline films of CuSc₁₋ₓMgₓO[subscript 2+y] are reported. Substitution of Mg for Sc systematically
increases the p-type conductivity in CuSc₁₋ₓMgₓO₂ sintered powders, producing a maximum
conductivity of 0.015 S/cm at x≈0.06. A similar level of conductivity is observed in transparent...
Transparent thin-film transistors (TTFTs) with an amorphous zinc tin oxide channel layer formed via rf magnetron sputter deposition are demonstrated. Field-effect mobilities of 5–15 and 20–50 cm² V‾¹ s‾¹ are obtained for devices post-deposition annealed at 300 and 600 °C, respectively. TTFTs processed at 300 and 600 °C yield devices...
We perform two-dimensional linear elastic finite element analysis to investigate the mechanical stability of ultrathin Ge/Si film grown on or bonded to SiO₂, using imperfect interface elements between Si and SiO₂ to model Si/SiO₂ interfacial slippage. We demonstrate that the overall composite film is stable when only the tangential slippage...