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arXiv · 1207.1502

Two-band superconductivity featuring different anisotropies in the ternary iron silicide Lu$_{2}$Fe$_{3}$Si$_{5}$

Y. Nakajima·H. Hidaka·T. Nakagawa·T. Tamegai·T. Nishizaki·T. Sasaki·N. Kobayashi
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Abstract

We report detailed studies of the upper critical field and low-temperature specific heat in the two-gap superconductor Lu$_{2}$Fe$_{3}$Si$_{5}$. The anisotropy of the upper critical field suggests that the active band is quasi-one-dimensional. Low-temperature specific heat in magnetic fields reveals that the virtual $H_{c2}$ in the passive band is almost isotropic. These results strongly indicate that the two bands have two different anisotropies, similar to the typical two-gap superconductor MgB$_{2}$, and their interplay may be essential to the two-gap superconductivity in Lu$_{2}$Fe$_{3}$Si$_{5}$.

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Y. Nakajima, H. Hidaka, T. Nakagawa, T. Tamegai, T. Nishizaki, T. Sasaki, N. Kobayashi. 2012-07-06. Two-band superconductivity featuring different anisotropies in the ternary iron silicide Lu$_{2}$Fe$_{3}$Si$_{5}$. https://doi.org/10.1103/physrevb.85.174524

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