8 papers
Exceptional activated mode theory for generalized real-complex transitions
Mengjie Yang, Alexander N. Poddubny, Ching Hua Lee
Real-to-complex spectral transitions mark the onset of amplification in non-Hermitian systems, but their thresholds are often treated as model-specific quantities. Here we develop…
Nonlocality-induced critical-length hierarchy from non-Hermitian competition
Mengjie Yang, Alexander N. Poddubny, Ching Hua Lee
Spectral transitions in non-Hermitian lattices often arise from the competition between non-reciprocal skin accumulation and inter-component hybridization. In short-range systems f…
Boundary Floquet Control of Bulk non-Hermitian Systems
Yu-Min Hu, Yu-Bo Shi, Linhu Li +5
Boundary perturbations are generally irrelevant for bulk properties in the thermodynamic limit, as they are edge-confined and subextensive. We show that this expectation breaks dow…
Occupation-selective topological pumping from Floquet gauge fields
Wenjie Liu, Ching Hua Lee, Zhoutao Lei
Topological pumping is conventionally governed by single-particle band topology. Here we show that promoting tunneling to a dynamical, occupation-conditioned variable fundamentally…
Beyond the non-Hermitian skin effect: scaling-controlled topology from Exceptional-Bound Bands
Mengjie Yang, Ching Hua Lee
We establish a novel mechanism for topological transitions in non-Hermitian systems that are controlled by the system size. Based on a new paradigm known as exceptional-bound (EB)…
Beyond symmetry protection: Robust feedback-enforced edge states in non-Hermitian stacked quantum spin Hall systems
Mengjie Yang, Ching Hua Lee
Conventional wisdom holds that, in the simplest time-reversal-symmetric setting, strongly coupling two QSH layers yields a trivial phase and no protected topological…