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arXiv · 1608.01190

Nuclear spin-lattice relaxation rate in noncentrosymmetric superconductor Y$_2$C$_3$

Chongju Chen·Biao Jin
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Abstract

For a noncentrosymmetric superconductor such as Y$_2$C$_3$, we consider a parity-mixing model composed of spin-singlet s-wave and spin-triplet f-wave pairing components. The $d$-vector in f-wave state is chosen to be parallel to the Dresselhaus asymmetric spin-orbit coupling vector. It is found that, the quasiparticle excitation spectrum exhibits distinct nodal structure as a consequence of parity-mixing. Our calculation predict anomalous noninteger power laws for low-temperature nuclear spin-lattice relaxation rate $T_{1}^{-1}$. We demonstrate particularly that such a model can qualitatively account for the existing experimental results of the temperature dependence of $T_{1}^{-1}$ in Y$_2$C$_3$.

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Chongju Chen, Biao Jin. 2016-08-03. Nuclear spin-lattice relaxation rate in noncentrosymmetric superconductor Y$_2$C$_3$. https://arxiv.org/abs/1608.01190

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