Photo induced enhancement of the Josephson effect in YBaCuO grain boundary junctions
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چکیده
Enhancement of conductivity and/or superconductivity has been found in YBa2CuaO~ thin films after illumination with visible light. 1-'t This persistent photoinduced conductivity (PPC) and photoinduced superconductivity (PPS) is maximum for deoxygenated samples and an insulating YBa2Cu:30~ thin film can even become superconducting by illumination, a In bicrystal grain boundary Josephson junctions, the grain boundary forming the weak link, is an YBa2CuaOz oxygen depleted region between two YBa2CuaOr banks. If these Josephson junctions are illuminated, the oxygen deficient region shows an enhancement of conductivity similar to YBa2CuaOz thin films. Thus, by photodoping, it is possible to change the weak coupling present in these Josephson junctions. This paper is devoted to a review of the effect of illumination on
منابع مشابه
Photodoping of YBaCuO Grain Boundary Josephson Junctions
coupling. In these GBJJ, the grain boundary which Since the discovery of High Tc Superconductivity constitutes the barrier is a weak superconducting at the end of 1986 [1], great attention has been paid region which is oxygen deficient andyor disordered. to the investigation of the action of light on High Tc Then, illumination of such junctions will change the Superconductors (HTSC). Besides th...
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