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arXiv · 2308.01081

Magnetization control of the nematicity direction and nodal points in a superconducting doped topological insulator

D. A. Khokhlov·R. S. Akzyanov·A. V. Kapranov
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Abstract

We study the effects of magnetization on the properties of the doped topological insulator with nematic superconductivity. We found that the direction of the in-plane magnetization fixes the direction of the nematicity in the system. The chiral state is more favorable than the nematic state for large values of out-of-plane magnetization. Overall, the critical temperature of the nematic state is resilient against magnetization. We explore the spectrum of the system with the pinned direction of the nematic order parameter $Δ_{y}$ in details. Without magnetization, there is a full gap in the spectrum. At strong enough out-of-plane $m_z$ or orthogonal in-plane $m_x$ magnetization, the spectrum is closed at the nodal points that are split by the magnetization. Flat Majorana surface states connect such split bulk nodal points. Parallel magnetization $m_y$ lifts nodal points and opens a full gap in the spectrum. We discuss relevant experiments and propose experimental verifications of our theory.

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D. A. Khokhlov, R. S. Akzyanov, A. V. Kapranov. 2023-08-02. Magnetization control of the nematicity direction and nodal points in a superconducting doped topological insulator. https://arxiv.org/abs/2308.01081

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