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arXiv · 1605.05563

Pairing mechanism of unconventional superconductivity in doped Kane-Mele model

Yuri Fukaya·Keiji Yada·Ayami Hattori·Yukio Tanaka
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Abstract

We study the pairing symmetry of a doped Kane-Mele model on a honeycomb lattice with on-site Coulomb interaction. The pairing instability of Cooper pair is calculated based on the linearized Eliashberg equation within the random phase approximation (RPA). When the magnitude of the spin-orbit coupling is weak, even-frequency spin-singlet even-parity (ESE) pairing is dominant. On the other hand, with the increase of the spin-orbit coupling, we show that the even-frequency spin-triplet odd-parity (ETO) f-wave pairing exceeds ESE one. ETO f-wave pairing is supported by the longitudinal spin fluctuation. Since the transverse spin fluctuation is strongly suppressed by spin-orbit coupling, ETO f-wave pairing becomes dominant for large magnitude of spin-orbit coupling.

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Yuri Fukaya, Keiji Yada, Ayami Hattori, Yukio Tanaka. 2016-05-18. Pairing mechanism of unconventional superconductivity in doped Kane-Mele model. https://doi.org/10.7566/jpsj.85.104704

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