6 papers
Biorthogonal scattering and generalized unitarity in non-Hermitian systems
Jung-Wan Ryu, Henning Schomerus, Hee Chul Park
We investigate the two-port scattering process in non-Hermitian dimer models via quantum measurements using external leads. We focus on two exemplary dimer models that preserve par…
Nonreciprocity induced spatiotemporal chaos: Reactive vs dissipative routes
Jung-Wan Ryu
Nonreciprocal interactions fundamentally alter the collective dynamics of nonlinear oscillator networks. Here we investigate Stuart-Landau oscillators on a ring with nonreciprocal…
A unified framework for exceptional point pairs in non-Hermitian two-level systems
Jung-Wan Ryu, Jae-Ho Han, Chang-Hwan Yi
Exceptional points (EPs) in non-Hermitian systems are branch singularities where eigenvalues and eigenvectors simultaneously coalesce, leading to rich topological phenomena beyond…
Non-orientable Exceptional Points in Twisted Boundary Systems
Jung-Wan Ryu, Jae-Ho Han, Moon Jip Park +2
Non-orientable manifolds, such as the Möbius strip and the Klein bottle, defy conventional geometric intuition through their twisted boundary conditions. As a result, topological d…
Decay Rates of Optical Modes Unveil the Island Structures in Mixed Phase Space
Chang-Hwan Yi, Barbara Dietz, Jae-Ho Han +1
We explore the decay rates of optical modes in asymmetric microcavities with mixed phase space across a wide range of wavelengths that extend deep into the semiclassical, i.e., sho…
Complex energy structures of exceptional point pairs in two level systems
Jung-Wan Ryu, Chang-Hwan Yi, Jae-Ho Han
We investigate the topological properties of multiple exceptional points in non-Hermitian two-level systems, emphasizing vorticity as a topological invariant arising from complex e…