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arXiv · 2106.03313

Robust quantum transport at particle-hole symmetry

Ipsita Mandal·Klaus Ziegler
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Abstract

We study quantum transport in disordered systems with particle-hole symmetric Hamiltonians. The particle-hole symmetry is spontaneously broken after averaging with respect to disorder, and the resulting massless mode is treated in a random-phase representation of the invariant measure of the symmetry-group. We compute the resulting fermionic functional integral of the average two-particle Green's function in a perturbation theory around the diffusive limit. The results up to two-loop order show that the corrections vanish, indicating that the diffusive quantum transport is robust. On the other hand, the diffusion coefficient depends strongly on the particle-hole symmetric Hamiltonian we choose to study. This reveals a connection between the underlying microscopic theory and the classical long-scale metallic behaviour of these systems.

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Ipsita Mandal, Klaus Ziegler. 2021-06-07. Robust quantum transport at particle-hole symmetry. https://doi.org/10.1209/0295-5075%2Fac1a25

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