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arXiv · 1704.01827

Magneto-elastic coupling model of deformable anisotropic superconductors

Abstract

We develop a magneto-elastic (ME) coupling model for the interaction between the vortex lattice and crystal elasticity. The theory extends the Kogan-Clem's anisotropic Ginzburg-Landau (GL) model to include the elasticity effect. The anisotropies in superconductivity and elasticity are simultaneously considered in the GL theory frame. We compare the field and angular dependences of the magnetization to the relevant experiments. The contribution of the ME interaction to the magnetization is comparable to the vortex-lattice energy, in materials with relatively strong pressure dependence of the critical temperature. The theory can give the appropriate slope of the field dependence of magnetization near the upper critical field. The magnetization ratio along different vortex frame axes is independent with the ME interaction. The theoretical description of the magnetization ratio is applicable only if the applied field moderately close to the upper critical field.

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Yingxu Li, Guozheng Kang, Yuanwen Gao. 2017-04-06. Magneto-elastic coupling model of deformable anisotropic superconductors. https://doi.org/10.1209/0295-5075%2F118%2F27006

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