English
Related papers

Related papers: Exceptional point induced unidirectional radiation…

200 papers

Exceptional points (EPs) have attracted extensive research interest due to their intriguing properties. One of the hallmarks of EP physics is that dynamically encircling the EPs induces chiral mode switching, arising from the breakdown of…

We study exceptional points (EPs) of a nonhermitian Hamiltonian $\hat{H}(\lambda,\delta)$ whose parameters $\lambda \in {\mathbb C}$ and $\delta \in {\mathbb R}$. As the real control parameter $\delta$ is varied, the $k$-th EP (or $k$-th…

Quantum Physics · Physics 2023-03-22 Milan Šindelka , Pavel Stránský , Pavel Cejnar

Motivated by the prospect of chiral-mode control in compact photonic systems, we analyze discrete coupled single-mode resonators. Using the minimal three-resonator model, we show that an infinitesimal complex onsite perturbation near a…

Optics · Physics 2026-05-18 Kota Yagi , Takahiro Uemura , Yuto Moritake , Adam Mock , Masaya Notomi

Dynamically encircling exceptional points (EPs) in two-dimensional Hamiltonian parameter space has enabled intriguing chiral dynamics in which the final state of the system depends on the encircling direction. Here, we show that full…

Optics · Physics 2022-10-05 Aodong Li , Lin Chen

Exceptional points are complex-valued spectral singularities that lead to a host of intriguing features such as loss-induced transparency - a counterintuitive process in which an increase in the system's overall loss can lead to enhanced…

Quantum Physics · Physics 2021-12-13 Konrad Tschernig , Kurt Busch , Demetrios N. Christodoulides , Armando Perez-Leija

The topological structure associated with the branchpoint singularity around an exceptional point (EP) provides new tools for controlling the propagation of electromagnetic waves and their interaction with matter. To date, observation of…

The unique properties of exceptional point (EP) singularities, arising from non-Hermitian physics, have unlocked new possibilities for manipulating light-matter interactions. A tailored gain-loss variation, while encircling higher-order EPs…

Non-Hermitian systems have recently attracted significant attention in photonics. One of the hallmarks of these systems is the possibility of realizing asymmetric mode switching and omnipolarizer action through the dynamic encirclement of…

Optics · Physics 2020-10-22 J. B. Khurgin , Y. Sebbag , E. Edrei , R. Zektzer , K. Shastri , U. Levy , F. Monticone

The current understanding of the role of topology in non-Hermitian (NH) systems and its far-reaching physical consequences observable in a range of dissipative settings are reviewed. In particular, how the paramount and genuinely NH concept…

Mesoscale and Nanoscale Physics · Physics 2021-03-03 Emil J. Bergholtz , Jan Carl Budich , Flore K. Kunst

Exceptional points, resulting from non-Hermitian degeneracies, have the potential to enhance the capabilities of quantum sensing. Thus, finding exceptional points in different quantum systems is vital for developing such future sensing…

Mesoscale and Nanoscale Physics · Physics 2020-01-22 Po-Chen Kuo , Neill Lambert , Adam Miranowicz , Hong-Bin Chen , Guang-Yin Chen , Yueh-Nan Chen , Franco Nori

We observe natural exceptional points in the excitation spectrum of an exciton-polariton system by optically tuning the light-matter interactions. The observed exceptional points do not require any spatial or polarization degrees of freedom…

Exceptional points (EPs) in non-Hermitian systems can give rise to intriguing effects not available in conventional Hermitian systems due to their unusual properties. Using full-wave simulations, we investigate the scattering, absorption,…

Classical Physics · Physics 2024-02-13 Chengzhi Zhang , Shubo Wang

Exceptional points (EPs) are remarkable spectral degeneracies in a non-Hermitian system's parameter space, where both eigenvalues and eigenstates coalesce. Here, we show that in non-Hermitian molecular chiral systems the position of EPs in…

Quantum Physics · Physics 2025-12-02 Nicola Mayer , Alexander Löhr , Nimrod Moiseyev , Misha Ivanov , Olga Smirnova

Exceptional points (EPs) are singularities in non-Hermitian systems, where the system transmission spectrum varies significantly at the phase transition point. Here, we propose a practical scheme to study the changes of the optomechanically…

Quantum Physics · Physics 2025-12-25 Y. Pan , H. -L. Zhang , Y. -F. Jiao , D. -Y. Wang , S. -L. Su , H. Jing

Exceptional points (EPs) are special spectral degeneracies of non-Hermitian operators: at the EP, the complex eigenvalues coalesce, i.e., they become degenerate in both their real and imaginary parts. In two-dimensional (2D) photonic…

Optics · Physics 2025-06-17 Luigi Frau , Simone Zanotti , Lydie Ferrier , Dario Gerace , Hai Son Nguyen

The intricate complex eigenvalues of non-Hermitian Hamiltonians manifest as Riemann surfaces in control parameter spaces. At the exceptional points (EPs), the degeneracy of both eigenvalues and eigenvectors introduces noteworthy topological…

Quantum Physics · Physics 2025-09-08 Sen Zhang , Yangyu Huang , Lei Yu , Kaixuan He , Ning Zhou , Dingbang Xiao , Xuezhong Wu , Franco Nori , Hui Jing , Xin Zhou

The amplitude of resonant oscillations in a non-Hermitian environment can either decay or grow in time, corresponding to a mode with either loss or gain. When two coupled modes have a specific difference between their loss or gain, a…

Classical Physics · Physics 2025-11-07 N. J. Lambert , A. Schumer , J. J. Longdell , S. Rotter , H. G. L. Schwefel

Exceptional points are complex branching singularities of non-Hermitian bands that have lately attracted considerable interest, particularly in non-Hermitian photonics. In this article, we review some recent developments in non-Hermitian…

Optics · Physics 2023-10-31 Haiyu Meng , Yee Sin Ang , Ching Hua Lee

The fascinating realm of non-Hermitian physics with the interplay of parity (P) and time-reversal (T) symmetry has been witnessing immense attention in exploring unconventional physics at Exceptional Point (EP) singularities. Particularly,…

Optics · Physics 2024-05-20 Dinesh Beniwal , Arnab Laha , Adam Miranowicz , Somnath Ghosh

Non-Hermitian operators are now routinely used to describe few-mode systems such as optical resonators and superconducting qubits, and exceptional points (EPs) are defective spectral singularities of such non-Hermitian operators. In…

Quantum Physics · Physics 2026-05-27 Okuto Morikawa , Shoya Ogawa , Soma Onoda