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The 𝐼-𝑉 characteristics and low frequency noises for indium zinc oxide thin film transistor are measured between 250 K and 430 K. The experimental results show that drain currents are thermally activated following the Meyer-Neldel rule, which can be explained by the multiple-trapping process. Moreover, the field effect electron mobility firstly increases, and then decreases with the increase of temperature, while the threshold voltage decreases with increasing the temperature. The activation energy and the density of localized gap states are extracted. A noticeable increase in the density of localized states is observed at the higher temperatures.

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Structural symmetry-breaking plays a crucial role in determining the second harmonic generation (SHG) intensity and pattern for two-dimensional (2D) materials. Herein, we report that the giant optical SHG can be achieved by designing a Janus structure for ReS2 and ReSe2. The designing of a Janus ReSSe monolayer structure can break both the in-plane and out-of-plane symmetry of monolayer ReS2 and ReSe2, resulting in the occurrence of larger second-order nonlinear coefficients in the in-plane (d 11, d 16, d 21, and d 22) and out-of-plane (d 15 and d 31) components. The second-order nonlinear coefficient dispersion properties for the asymmetric Janus ReSSe monolayer give rise to a multifaceted dependence of the SHG on the azimuthal and polarization angles at different incident wavelengths including double and quadruple symmetries, rotation of polar axis, and variations in intensity. These results highlight the potential to deterministically engineer novel nonlinear optical properties in the designing of the Janus structure based on layered materials.

The water-gated thin-film transistor (TFT) was demonstrated with In2O3 channel grown by metal–organic chemical vapor deposition (MOCVD) for visible-blind ultraviolet (UV) detection application. The simple water-gated TFT displays great photocurrent responsivity in depletion state (∼5300 A W−1 at wavelength of 280 nm). The UV–visible rejection ratio is as high as 105. Additionally, the UV detector shows great repeatability with fast response and a decay time of 0.2 s despite the low operation voltage (≤1 V). The performance could be attributed to the band-to-band photon emission in the polycrystalline In2O3 channel prepared by MOCVD and the large capacitance of water dielectric gate.