Selective and tunable excitation of topological non-Hermitian skin modes
arXiv:2112.04988 · doi:10.1098/rspa.2021.0927
Abstract
Non-Hermitian lattices under semi-infinite boundary conditions sustain an extensive number of exponentially-localized states, dubbed non-Hermitian skin modes. Such states can be predicted from the nontrivial topology of the energy spectrum under periodic boundary conditions via a bulk-edge correspondence. However, the selective excitation of the system in one among the infinitely-many topological skin edge states is challenging both from practical and conceptual viewpoints. In fact, in any realistic system with a finite lattice size most of skin edge states collapse and become metastable states. Here we suggest a route toward the selective and tunable excitation of topological skin edge states which avoids the collapse problem by emulating semi-infinite lattice boundaries via tailored on-site potentials at the edges of a finite lattice. We illustrate such a strategy by considering a non-Hermitian topological interface obtained by connecting two Hatano-Nelson chains with opposite imaginary gauge fields, which is amenable for a full analytical treatment.
14 pages, 7 figures, under review by Proceedings of the Royal Society A
References in corpus (20)
- Topological Photonics
- Topological Origin of Non-Hermitian Skin Effects
- Efficient Light Funneling based on the non-Hermitian Skin Effect
- Edge Modes, Degeneracies, and Topological Numbers in Non-Hermitian Systems
- Critical non-Hermitian Skin Effect
- Topological phase transition in non-Hermitian quasicrystals
- New topological invariants in non-Hermitian systems
- Observation of higher-order non-Hermitian skin effect
- Observation of arbitrary topological windings of a non-Hermitian band
- A General Theorem Relating the Bulk Topological Number to Edge States in Two-dimensional Insulators
- Exact solution of non-Hermitian systems with generalized boundary conditions: size-dependent boundary effect and fragility of skin effect
- Defining a bulk-edge correspondence for non-Hermitian Hamiltonians via singular-value decomposition
- Knots and Non-Hermitian Bloch Bands
- Non-Bloch band collapse and chiral Zener tunneling
- Anomalous topological edge states in non-Hermitian piezophononic media
- Detecting non-Bloch topological invariants in quantum dynamics
- Ultrafast and Anharmonic Rabi Oscillations between Non-Bloch-Bands
- Non-Markovian Decay and Lasing Condition in an Optical Microcavity Coupled to a Structured Reservoir
- Bulk-edge correspondence and trapping at a non-Hermitian topological interface
- Self-healing of non-Hermitian topological skin modes