Khan Masood Rauf, Leo Antonio, Nigro Angela, Galluzzi Armando, Polichetti Massimiliano, Braccini Valeria, Cialone Matteo, Scuderi Mario, Grimaldi Gaia
Physics Department "E. R. Caianiello", University of Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano, Italy.
CNR SPIN Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano, Italy.
Materials (Basel). 2021 Sep 14;14(18):5289. doi: 10.3390/ma14185289.
The role of a layered structure in superconducting pinning properties is still at a debate. The effects of the vortex shape, which can assume for example a staircase form, could influence the interplay with extrinsic pinning coming from the specific defects of the material, thus inducing an effective magnetic field dependence. To enlighten this role, we analysed the angular dependence of flux pinning energy (,) as a function of magnetic field in FeSeTe thin film by considering the field components along the -plane of the crystal structure and the -axis direction. (,) has been evaluated from magneto-resistivity measurements acquired at different orientations between the applied field up to 16 T and FeSeTe thin films grown on a CaF substrate. We observed that the (,) shows an anisotropic trend as a function of both the intensity and the direction of the applied field. Such a behaviour can be correlated to the presence of extended defects elongated in the -planes, thus mimicking a layered superconductor, as we observed in the microstructure of the compound. The comparison of FeSeTe with other superconducting materials provides a more general understanding on the flux pinning energy in layered superconductors.
层状结构在超导钉扎特性中的作用仍存在争议。涡旋形状的影响，例如它可以呈现阶梯状，可能会影响与来自材料特定缺陷的外在钉扎的相互作用，从而引起有效的磁场依赖性。为了阐明这一作用，我们通过考虑沿晶体结构的 - 平面和 - 轴方向的场分量，分析了FeSeTe薄膜中磁通钉扎能量(,) 作为磁场函数的角度依赖性。(,) 是根据在高达16 T的外加磁场与生长在CaF衬底上的FeSeTe薄膜之间不同取向时获得的磁阻测量值来评估的。我们观察到，(,) 作为外加磁场强度和方向的函数呈现各向异性趋势。这种行为可以与在 - 平面中伸长的扩展缺陷的存在相关联，从而模拟层状超导体，正如我们在该化合物的微观结构中所观察到的那样。将FeSeTe与其他超导材料进行比较，可以更全面地了解层状超导体中的磁通钉扎能量。
