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arXiv · 1501.06677

Orbital angular momentum in a nonchiral topological superconductor

Atsuo Shitade·Yuki Nagai
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Abstract

We investigate the bulk orbital angular momentum in a two-dimensional time-reversal broken topological superconductor with the Rashba spin-orbit interaction, the Zeeman interaction, and the $s$-wave pairing potential. Prior to the topological phase transition, we find the crossover from $s$ wave to $p$ wave. For the large spin-orbit interaction, even in the topological phase, $L_z/N$ does not reach $-1/2$, which is the intrinsic value in chiral $p$-wave superconductors. Here $L_z$ and $N$ are the bulk orbital angular momentum and the total number of electrons at zero temperature, respectively. Finally, we discuss the effects of nonmagnetic impurities.

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Atsuo Shitade, Yuki Nagai. 2015-07-07. Orbital angular momentum in a nonchiral topological superconductor. https://doi.org/10.1103/physrevb.92.024502

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