The metal-insulator transition (MIT) in strong correlated electron materials can be induced by external perturbation in forms of thermal, electrical, optical, or magnetic fields. We report on the DC current induced MIT in epitaxial Sm0.6Nd0.4NiO3 (SNNO) thin film deposited by pulsed laser deposition on (001)-LaAlO3 substrate. It was found that the MIT in SNNO film not only can be triggered by thermal, but also can be induced by DC current. The TMI of SNNO film decreases from 282 K to 200 K with the DC current density increasing from 0.003 × 109 A•m−2 to 4.9 × 109 A•m−2. Based on the resistivity curves measured at different temperatures, the MIT phase diagram has been successfully constructed.

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A novel technology based on aluminium gallium nitride (AlGaN)/GaN hybrid-anode diode (HAD) for precise modulation of turn-on voltage is proposed and experimentally demonstrated. By delicately tailoring the as-grown barrier thickness, the turn-on voltage of the HAD and yet the non-linearity at zero bias (i.e. 0 V) for efficient microwave detection can be flexibly modulated. An AlGaN/GaN ultra-thin-barrier HAD (UTB-HAD) was designed and fabricated for zero-bias microwave detection. The AlGaN-barrier thickness was optimised to be 5 nm by TCAD simulation, which yields a strong non-linearity at zero bias featuring a high-curvature coefficient (γ) of 27 V −1 in the fabricated UTB-HAD. The first-order voltage sensitivity β V is projected to be as high as 2.7 mV/μW. The proposed approach of precise sensitivity modulation is of great interests for high-efficient zero-bias microwave detection applications.

Double-doped La 0.67 Ca 0.33-x Sr x MnO 3 (x=0, 0.05, 0.15) powders were synthesized by traditional solid-state reaction method. Effects of sintering temperature on structure, micro morphology and metal-insulator phase transition temperature of La 0.67 Ca 0.33-x Sr x MnO 3 ceramic were systemically studied. The results showed that sintering temperature had little influence on crystallinity or micro morphology of as-prepared ceramic, while double-doping effectively changed the phase transition temperature of the ceramics. When the ceramics sintered at 1400 , ℃ the metal-insulator phase transition temperature increased from-20℃ to 6℃ and the ceramics stabilized in orthorhombic structure as the doping level varing from x=0 to x=0.05. At the doping level x=0.15, the crystal structure changed from rhombohedral to orthorhombic and the metal-insulator transition temperature was 17℃. Under the same doping concentration, the metal-insulator phase transition temperature of the ceramics increased with the increase of sintering temperature. The above mentioned material may be an ideal candidate for active thermal control technology of long life satellites.