Quantum strain sensor with a topological insulator HgTe quantum dot

Marek Korkusinski; Pawel Hawrylak

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arXiv · 1405.2285

Quantum strain sensor with a topological insulator HgTe quantum dot

Marek Korkusinski·Pawel Hawrylak

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Abstract

We present a theory of electronic properties of HgTe quantum dot and propose a strain sensor based on a strain-driven transition from a HgTe quantum dot with inverted bandstructure and robust topologically protected quantum edge states to a normal state without edge states in the energy gap. The presence or absence of edge states leads to large on/off ratio of conductivity across the quantum dot, tunable by adjusting the number of conduction channels in the source-drain voltage window. The electronic properties of a HgTe quantum dot as a function of size and applied strain are described using eight-band kp Luttinger and Bir-Pikus Hamiltonians, with surface states identified with chirality of Luttinger spinors and obtained through extensive numerical diagonalization of the Hamiltonian.

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Marek Korkusinski, Pawel Hawrylak. 2014-05-09. Quantum strain sensor with a topological insulator HgTe quantum dot. https://arxiv.org/abs/1405.2285

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