【摘要】 利用紫外脉冲激光源淀积生长氧化物薄膜的技术，我们在ＳｉＴｉＯ３衬底上成功地外延生长了超薄超导ＹＢａ０．２Ｃｕ３Ｏ７薄膜样品．样品ＹＢａ０．２Ｃｕ３Ｏ７层厚度分别为２．４ｎｍ至１０．８ｎｍ（二至九个原胞）．四端引线电阻法测量了样品的电阻温度关系和超导转变．超导零电阻温度分别为１６Ｋ至８１Ｋ．超薄超导薄膜样品显示当ＹＢａ０．２Ｃｕ３Ｏ７层厚度达到和超过四个原胞层厚（９．６ｎｍ）时，厚度变化对样品超导零电阻转变的影响并不十分明显．实验观察到ＹＢａ０．２Ｃｕ３Ｏ７层厚度对样品超导零电阻温度和超导起始转变影响不同．这说明样品中的缺陷对样品性能有着不容忽视的影响．超薄ＹＢａ０．２Ｃｕ３Ｏ７超导薄膜样品的成功制备为进一步的研究提供了有利条件．更多还原

【Abstract】 Abstract We present our experimental results on the normal resistances and superconducting transitions in ultra thin YBa 2Cu 3O 7(YBCO) films with thicknesses from 2.4 to 1.08nm (corresponding from two to nine unit cells, respectively). The ultra thin YBCO films fabricated on (100) SrTiO 3 substrates by pulsed laser deposition show superconducting transition with T c (0) from 16K to 81K. The in plane ρ ab behaviors and superconducting transition of the ultra thin films are strong dependent on the YBCO thicknesses. The different influences of the YBCO thicknesses on the T c (0), T onset c and resistance behaviors of the samples were discuss.更多还原