Spin Diffusion Length at Interface of Sm1-xSrxMnO3 and YBa2Cu3O7
S. L. CHENG1,2, T. H. CHUANG2, J. G. LIN1*
1Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan
2Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan
* Presenter:J. G. LIN
We report a detailed study on the spin diffusion length of ferromagnetic Sm1-xSrxMnO3 (SSMO)/superconducting YBa2Cu3O7 (YBCO) bilayers. The bilayer structure is composed of a SSMO layer of 10 nm with varying the YBCO thicknesses (d) from 10 to 50 nm. The measurements of x-ray diffraction/reflectivity, resistivity and magnetization were carried out for determining the crystalline and the superconducting temperatures Tc of YBCO single layers and bilayers. A significant suppression of Tc is observed when YBCO(d) layer is capped on the top of SSMO for d < 10 nm. The d-dependent suppression of Tc allows us to obtain the spin diffusion length of polarized quasiparticles diffusing into YBCO layer from ferromagnetic SSMO. Based on the results of simulation, the spin diffusion length of Sm1-xSrxMnO3 with x = 33 and 45 are determined to be 5 and 4 nm respectively.

This work is financially supported in part by Minister of Science and technology of R. O. C. with the project no. 105-2112-M-002-010-MY3.

Keywords: spin diffusion length, magnetic SSMO, superconducting YBCO