Hysteresis and the single-phase metal-insulator transition in switchable YHx films

Article

关键词: LANTHANUM HYDRIDE FILMS;    OPTICAL-PROPERTIES;    SEMICONDUCTOR TRANSITIONS;    ELECTRONIC-STRUCTURE;    HYDROGEN INSERTION;    MIRRORS;    YTTRIUM;    TRANSMISSION;    SPECTROSCOPY;    DIFFRACTION;   

DOI  :  10.1103/PhysRevB.62.10088

来源: SCIE

【 摘 要 】

Extraordinary large hysteresis effects in optical, electrical, and structural properties are observed in switchable mirrors based on thin yttrium hydride (YHx) films, deposited on quartz, glass or sapphire. The pressure-composition isotherms of the YHx system between x=2 and 3 for absorption and desorption, determined electrochemically, differ by approximately three orders of magnitude. The optical transmittance exhibits a distinct minimum when loading the films from the dihydride to the trihydride state; however, upon unloading this minimum is absent. The desorption data are in good agreement with literature data on bull; yttrium, but the absorption results show large deviations. Most important for the metal-insulator transition is that during hydrogen loading YHx remains in a single hcp phase for x>2.1. The hysteresis is discussed in terms of strains (and consequently stress) at the interface between fee dihydride and hcp trihydride.

【 授权许可】

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