Comparison of the pinning energy in Fe(Se1?xTex) compound between single crystals and thin films

11th European Conference on Applied Superconductivity

Leo, A.^1 ; Guarino, A.^1 ; Grimaldi, G.^1 ; Nigro, A.^1 ; Pace, S.^1 ; Bellingeri, E.^2 ; Kawale, S.^2 ; Ferdeghini, C.^2 ; Giannini, E.^3

CNR-SPIN Salerno and Dipartimento di Fisica 'E R Caianiello', Universitá di Salerno, Via Giovanni Paolo II, 132, Fisciano (SA)

I-84084, Italy^1

CNR-SPIN Genova, corso Perrone 24, Genova

I-16152, Italy^2

Department de Physique de la Matiere Condensee, Universite de Geneve, Quai Ernest-Ansermet 24, Geneve

1211, Switzerland^3

关键词: Anisotropy analysis;    Current voltage measurement;    Different substrates;    Epitaxial thin films;    Influence of magnetic field;    Parallel configuration;    Pinning mechanism;    Power-law dependences;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/1/012029/pdf
DOI  :  10.1088/1742-6596/507/1/012029

来源: IOP

【 摘 要 】

Among the families of iron-based superconductors, we investigate flux pinning mechanisms in the Fe(Se1-xTex) compound. We perform magneto-resistance and current-voltage measurements on single-crystals, as well as on several epitaxial thin films grown on different substrates (CaF2, LaAlO3). The activation energy is derived as a function of magnetic field, U(H). The influence of magnetic field orientation on the pinning energy activation mechanism is also studied, leading to the anisotropy analysis which reveals low anisotropy in thin films grown on CaF2substrate with respect to single crystals and films grown on LaAlO3. Concerning the dominant pinning regime, the exponents of the power law dependence U0(H) ∝ H-αhave been evaluated, confirm that weak pinning is a general characteristic of this compound. The single exponent feature, generally noticed on thin films grown on SrTiO3substrate and associated to a strong single vortex regime, has been observed in thin films grown on LaAlO3, only in the parallel configuration. At the end, this overall comparison can be useful to develop a technological material able to compete with high temperature superconductors.