Low-energy effective Hamiltonian and end states of an inverted HgTe nanowire

Rui Li

doi:10.1016/j.physe.2025.116354

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arXiv · 2505.07478

Low-energy effective Hamiltonian and end states of an inverted HgTe nanowire

Rui Li

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Abstract

The band inversion transition in a cylindrical HgTe nanowire is inducible via varying the nanowire radius. Here we derive the low-energy effective Hamiltonian describing the band structure of the HgTe nanowire close to the fundamental band gap. Because both the $E_{1}$ and $H_{1}$ subbands have quadratic dependence on $k_{z}$ when the gap closes, we need to consider at least three subbands, i.e., the $E_{1}$, $H_{1}$, and $H_{2}$ subbands, in building the effective Hamiltonian. The resulting effective Hamiltonian is block diagonal and each block is a $3\times3$ matrix. End states are found in the inverted regime when we solve the effective Hamiltonian with open boundary condition.

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Rui Li. 2025-08-31. Low-energy effective Hamiltonian and end states of an inverted HgTe nanowire. https://doi.org/10.1016/j.physe.2025.116354

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