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Indium tin oxide (ITO) film, which is the most commonly used transparent conductive film (TCF), has traditionally been believed to be transparent in the visible spectrum but to reflect infrared (IR) light beyond the plasma wavelength (λp). However, our theoretical analysis challenges this notion by demonstrating that an ultrathin ITO TCF that is thinner than the light's penetration depth can overcome the transmission barrier at λp. To validate the theoretical modeling, we have successfully fabricated ultrathin ITO films that, despite having λp ≈ 1 μm, remain transparent from 400 nm to 20 μm. This represents the broadest transparency range ever reported for any In2O3-based TCF. The 10-nm-thick ITO TCFs have high visible transmittance (91.0% at 550 nm), low resistivity (5 × 10−4 Ω cm), and good IR transmittance (averaging 60% over 1.35–18.35 μm). Their IR transparency facilitates radiative cooling of the underlying circuitry. When an operational resistor is enclosed by commercial ITO TCFs that are 140 nm thick, its temperature increases. However, using 10-nm-thick ITO TCFs instead of the commercial ones can completely avoid this temperature rise. Moreover, attaching a silver grid to a 10-nm-thick ITO TCF can reduce the effective sheet resistance to ∼10 Ω/□ at the expense of only ∼3% transmittance. This development paves the way for large-scale applications that require low sheet resistance and far-IR transparency. [ABSTRACT FROM AUTHOR]

Metal-trihalide perovskite quantum dots combine the unique semiconducting properties of bulk perovskites with the controllable exciton dynamics benefiting from the quantum confinement effect. Composition- and size-adjustable electronic and optical properties of perovskites convert into a variety of applications. Here, we start from a brief introduction to perovskite quantum dots, followed by a detailed description of the synthesis methods and surface modification/passivation strategies of these nano-sized particles. Then, we review the applications of perovskite quantum dots including light-emitting diodes, photovoltaics, catalysis, sensing, bioimaging, and lasers. Finally, we develop outlooks for promising futures toward the commercial application of perovskite quantum dots. [ABSTRACT FROM AUTHOR]

A high-speed creep process mediated by rapid dislocation absorption was found in the nanoindentation creep test on nanocrystalline Cu. The creep strain and creep strain rate depend strongly on the loading strain rate and are far higher than those predicted by the models of Coble creep and thermally activated grain boundary sliding. Our analysis revealed that grain boundary dislocation sources can be activated and emitted dislocations from grain boundaries can be stored effectively at a high loading strain rate, but cannot at a low loading strain rate. The observed high-speed creep process is mediated mainly by the rapid absorptions of the stored dislocations and the dislocations newly nucleated during the holding period. An implication of our experimental finding is that dislocation structure in nanocrystalline metals is highly unstable and dislocation activity can proceed after loading and lead to a significant post-loading plasticity. [ABSTRACT FROM AUTHOR]

We investigate the electronic and thermoelectric properties of GeTe in both cubic and rhombohedral phases. We find that cubic GeTe has an electronic structure with a narrow band gap that is unfavorable at high temperature, where the cubic phase is normally stable. However, cubic GeTe has electronic features that may lead to p-type performance superior to the normal rhombohedral phase at lower temperature. This is explained in part by the combination of light and heavy band character that is very effective in obtaining high thermopower and conductivity. In addition, the valence band edge carrier pockets in cubic GeTe possess the largest anisotropy among cubic IV-VI analogs. These effects are stronger than the effect of band convergence in the rhombohedral structure. The results suggest further study of stabilized cubic GeTe as a thermoelectric. [ABSTRACT FROM AUTHOR]