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arXiv · 1804.00579

Linear localization of zero modes in weakly coupled non-Hermitian reservoirs

Bingkun Qi·Li Ge
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Abstract

Topological and symmetry-protected non-Hermitian zero modes have attracted considerable interest in the past few years. Here we reveal that they can exhibit an unusual behavior when transitioning between the extended and localized regimes: When weakly coupled to a non-Hermitian reservoir, such a zero mode displays a linearly decreasing amplitude as a function of space, which is not caused by an EP of a Hamiltonian, either of the entire system or the reservoir itself. Instead, we attribute it to the non-Bloch solution of a linear homogeneous recurrence relation, together with the underlying non-Hermitian particle-hole symmetry and the zeroness of its energy.

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Bingkun Qi, Li Ge. 2018-04-02. Linear localization of zero modes in weakly coupled non-Hermitian reservoirs. https://doi.org/10.1002/apxr.202300066

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