【摘要】 采用在Nb掺杂钛酸锶(strontlum tltanate,SrTiO3,STO)衬底上沉积La1-xSrxCuO4(x为摩尔分数)薄膜的方法,制备不同Sr掺量的系列La1-xSrxCuO4/Nb-SrTiO3(LSCO/NSTO)异质结构材料。对LSCO/NSTO整流曲线的研究发现:当低于超导转变温度,在La1-xSrxCuO4处于过掺杂与欠掺杂两种状态时,扩散势的变化(ΔVd)极大不同。由于ΔVd系超导能隙(Eg)的打开所致,ΔVd的变化也反映超导能隙与空穴掺杂浓度的依赖关系,对欠掺杂和过掺杂两种不同掺杂范围的相关行为的研究结果与其他理论的观点具有很好的一致性。更多还原

【Abstract】 La1–xSrxCuO4 (LSCO)/Nb-doped SrTiO3 (NSTO) junctions were created by growing systematically doped LSCO films on NSTO single-crystal substrates. In rectifying curves,variation of diffusion potential (ΔVd) below transition temperature of the LSCO was found to be very different in under-and over-doped regimes upon hole doping. Because ΔVd was caused by opening of super-conducting gap (Eg),development of ΔVd reveals the development of Eg with hole doping. The cases in these two doped regimes are discussed in details. The results agree well to generally perceived points obtained by the other methods. The study in presented work provided a convenient and alternative route for exploring the developments of Eg in the high-temperature superconductors with hole doping.更多还原