Suppression of one-dimensional weak localization by band asymmetry

• URL: http://arxiv.org/abs/2302.13816v2
• Date: Thu, 24 Aug 2023 06:12:55 GMT
• Title: Suppression of one-dimensional weak localization by band asymmetry
• Authors: Kartikeya Arora, Rajeev Singh, Pavan Hosur
• Abstract summary: We investigate disorder-induced localization in metals that break time-reversal and inversion symmetries through their energy dispersion. In the perturbative regime of disorder, we show that weak localization is suppressed due to a mismatch of the Fermi velocities of left and right movers.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We investigate disorder-induced localization in metals that break time-reversal and inversion symmetries through their energy dispersion, $\epsilon_{k}\neq\epsilon_{-k}$, but lack Berry phases. In the perturbative regime of disorder, we show that weak localization is suppressed due to a mismatch of the Fermi velocities of left and right movers. To substantiate this analytical result, we perform quench numerics on chains shorter than the Anderson localization length -- the latter computed and verified to be finite using the recursive Green's function method -- and find a sharp rise in the saturation value of the participation ratio due to band asymmetry, indicating a tendency to delocalize. Interestingly, for weak disorder strength $\eta$, we see a better fit to the scaling behavior $\xi\propto1/\eta^{2}$ for asymmetric bands than conventional symmetric ones.

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