Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation
Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation
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DOI：
10.1103/physrevb.75.024511
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发表时间：
2007
影响因子：
3.7
通讯作者：
H. Oyanagi;A. Tsukada;A. Tsukada;M. Naito;N. Saini
中科院分区：
文献类型：
--
作者：
H. Oyanagi;A. Tsukada;A. Tsukada;M. Naito;N. Saini
(La,Sr){sub 2}CuO{sub 4} 薄膜单晶的高质量偏振 X 射线吸收光谱数据揭示了与超导临界温度相关的应变依赖性局部无序（在氧径向分布中）。与温度相关的面内氧位移表明，局部晶格畸变强烈依赖于应变，即双轴拉伸应变形成具有键拉伸型局部畸变的域，而压缩应变削弱了这种局部畸变。我们认为二维应变改变了通过超流体密度而不是能带结构效应影响超导临界温度的电子不均匀性。
High-quality polarized x-ray absorption spectroscopy data for (La,Sr){sub 2}CuO{sub 4} thin-film single crystals reveal strain-dependent local disorder (in the oxygen radial distribution) that correlates with the superconducting critical temperature. The temperature-dependent in-plane oxygen displacement shows that local lattice distortion strongly depends on strain, i.e., the biaxial tensile strain develops domains with the bond-stretching-type local distortion which is weakened by the compressive strain. We suggest that the two-dimensional strain modifies electronic inhomogeneity that influences the superconducting critical temperature through superfluid density, rather than band structure effects.