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arXiv · 1601.03499

Non-Hermitian tight-binding network engineering

Stefano Longhi
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Abstract

We suggest a simple method to engineer a tight-binding quantum network based on proper coupling to an auxiliary non-Hermitian cluster. In particular, it is shown that effective complex non-Hermitian hopping rates can be realized with only complex on-site energies in the network. Three applications of the Hamiltonian engineering method are presented: the synthesis of a nearly transparent defect in an Hermitian linear lattice; the realization of the Fano-Anderson model with complex coupling; and the synthesis of a $\mathcal{PT}$-symmetric tight-binding lattice with a bound state in the continuum.

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Stefano Longhi. 2016-01-14. Non-Hermitian tight-binding network engineering. https://doi.org/10.1103/physreva.93.022102

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