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arXiv · 2409.00274

Spin-orbit control of Dirac points and end states in inverted gap nanowires

Andrea Vezzosi·Andrea Bertoni·Marco Gibertini·Guido Goldoni
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Abstract

We predict that in InAs/GaSb nanowires with an inverted band alignment a transverse electric field induces a collapse of the hybridization gap, and a semimetal phase occurs. We use a self-consistent k.p approach and an adapted Bernevig-Hughes-Zhang model to show that massless Dirac points result from exact cancellation between the kinetic electron-hole coupling and the field-controlled spin-orbit coupling. End states - mid-gap states localized at the extremes of a finite nanowire - are supported up to a critical field, but suddenly fade away as the system is driven through the semimetal phase, eventually evolving to trivial surface states, which expose a spin-orbit induced topological transition to the normal phase.

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Andrea Vezzosi, Andrea Bertoni, Marco Gibertini, Guido Goldoni. 2024-08-30. Spin-orbit control of Dirac points and end states in inverted gap nanowires. https://arxiv.org/abs/2409.00274

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