activity
20102026
most citedUnidirectional Nonlinear PT-symmetric Optical Structures

685 citations · 2.5k across the 38 of their papers we have counts for

collaborators

39 papers

physics.optics2026

Biorthogonality of Guided Modes in Non-Hermitian Electromagnetism

Amgad Abdrabou, M. A. Swillam, Şahin K. Özdemir +1

Biorthogonality plays a central role in the analysis of non-Hermitian photonic systems, where modal expansions generally require both right and left eigenstates. While these concep…

physics.optics2025

-like phase transitions from square roots of supersymmetric Hamiltonians

Jacob L. Barnett, Ramy El-Ganainy

We introduce a general framework for realizing -like phase transitions in non-Hermitian systems without imposing explicit parity--time () symmetry. The…

cond-mat.mes-hall2025

Non-Hermitian Dynamics in Quantum Anomalous Hall Insulators

Le Yi, Emma Steinebronn, Asmaul Smitha Rashid +4

Magnetically doped topological insulators (TIs) exhibit two distinct phases: the quantum anomalous Hall (QAH) phase when the Fermi level resides within the surface gap, and a metal…

physics.optics2024

A topological route to engineering robust and bright supersymmetric laser arrays

Soujanya Datta, Mohammadmahdi Alizadeh, Ramy El-Ganainy +1

In recent years, several proposals that leverage principles from condensed matter and high-energy physics for engineering laser arrays have been put forward. The most important amo…

physics.optics2023★ 53 cited

Resolving the topology of encircling multiple exceptional points

Chitres Guria, Qi Zhong, Sahin K. Ozdemir +3

Non-Hermiticity has emerged as a new paradigm for controlling coupled-mode systems in ways that cannot be achieved with conventional techniques. One aspect of this control that has…

physics.optics2022

Tracking exceptional points above laser threshold

Kaiwen Ji, Qi Zhong, Li Ge +5

Recent studies on non-Hermitian optical systems having exceptional points (EPs) have revealed a host of unique characteristics associated with these singularities, including unidir…

physics.optics2022

Non-universality of quantum noise in optical amplifiers operating at exceptional points

L. Simonson, S. K. Ozdemir, A. Eisfeld +2

The concept of exceptional points-based optical amplifiers (EPOAs) has been recently proposed as a new paradigm for miniaturizing optical amplifiers while simultaneously enhancing…

physics.optics2022★ 1 cited

The missing link between standing- and traveling-wave resonators

Qi Zhong, Haoqi Zhao, Liang Feng +3

Optical resonators are structures that utilize wave interference and feedback to confine light in all three dimensions. Depending on the feedback mechanism, resonators can support…

physics.optics2022★ 48 cited

Linear response theory of open systems with exceptional points

A. Hashemi, K. Busch, D. N. Christodoulides +2

Understanding the linear response of any system is the first step towards analyzing its linear and nonlinear dynamics, stability properties, as well as its behavior in the presence…

physics.optics2021★ 153 cited

Chiral Coherent Perfect Absorption on Exceptional Surfaces

S. Soleymani, Q. Zhong, M. Mokim +3

Engineering the transport of radiation and its interaction with matter using non-Hermiticity, particularly through spectral degeneracies known as exceptional points(EPs), is an eme…

physics.optics2021★ 19 cited

New perspective on chiral exceptional points with application to discrete photonics

A. Hashemi, S. M. Rezaei, S. K. Ozdemir +1

Chiral exceptional points (CEPs) have been shown to emerge in traveling wave resonators via asymmetric back scattering from two or more nano-scatterers. Here, we provide a new pers…

physics.app-ph2021★ 3 cited

Experimental observation of PT symmetry breaking near divergent exceptional points

M. Sakhdari, M. Hajizadegan, Q. Zhong +3

Standard exceptional points (EPs) are non-Hermitian degeneracies that occur in open systems. At an EP, the Taylor series expansion becomes singular and fails to converge -- a featu…

physics.optics2020★ 88 cited

Hierarchical construction of higher-order exceptional points

Q. Zhong, J. Kou, S. K. Ozdemir +1

The realization of higher-order exceptional points (HOEPs) can lead to orders of magnitude enhancement in light-matter interactions beyond the current fundamental limits. Unfortuna…

physics.optics2020★ 42 cited

Control of spontaneous emission dynamics in microcavities with chiral exceptional surfaces

Q. Zhong, A. Hashemi, S. K. Ozdemir +1

We investigate spontaneous emission from a quantum emitter located within the mode volume of a microring resonator that features chiral exceptional points. We show that this config…

physics.optics2020★ 17 cited

Coherent virtual absorption of light in microring resonators

Q. Zhong, L. Simonson, T. Kottos +1

Light trapping and radiation process from linear reciprocal photonic resonators is one of the fundamental processes in optical science and engineering. Recently, the concept of coh…

physics.optics2019★ 73 cited

Direct generation of tunable orbital angular momentum beams in microring lasers with broadband exceptional points

William E. Hayenga, Jinhan Ren, Midya Parto +7

Non-Hermitian exceptional points (EPs) represent a special type of degeneracy where not only the eigenvalues coalesce, but also the eigenstates tend to collapse on each other. Rece…

quant-ph2019

Reply to "Comment on `Winding around non-Hermitian singularities' by Zhong et al., Nat. Commun. 9, 4808 (2018)"

Q. Zhong, M. Khajavikhan, D. N. Christodoulides +1

A comment has been recently posted on the arXiv (arXiv:1902.07504) that discuss our recent work on encircling multiple exceptional points in Nat. Commun. 9, 4808 (2018). In that co…

quant-ph2019★ 5 cited

Non-Hermitian engineering for brighter broadband pseudothermal light

Nicolás Quesada, Eugene Adjei, Ramy El-Ganainy +1

We show that non-Hermitian engineering can play a positive role in quantum systems. This is in contrast to the widely accepted notion that optical losses are a foe that must be eli…

physics.optics2018★ 123 cited

Supersymmetric Laser Arrays

Mohammad P. Hokmabadi, Nicholas S. Nye, Ramy El-Ganainy +2

The theoretical framework of supersymmetry (SUSY) aims to relate bosons and fermions -- two profoundly different species of particles -- and their interactions. While this space-ti…

physics.optics2018

Generalized Parity-Time Symmetry Condition for Enhanced Sensor Telemetry

Pai-Yen Chen, Maryam Sakhdari, Mehdi Hajizadegan +4

Wireless sensors based on micro-machined tunable resonators are important in a variety of applications, ranging from medical diagnosis to industrial and environmental monitoring.Th…

physics.optics2018

Experimental Realization of Multiple Topological Edge States in a One-Dimensional Photonic Lattice

Zhifeng Zhang, Mohammad Teimourpour, Jake Arkinstall +5

Topological photonic systems offer light transport that is robust against defects and disorder, promising a new generation of chip-scale photonic devices and facilitating energy-ef…

physics.optics2018★ 263 cited

Sensing with exceptional surfaces: combining sensitivity with robustness

Q. Zhong, J. Ren, M. Khajavikhan +3

Exceptional points (EPs) are singularities that arise in non-Hermitian physics. Current research efforts focus only on systems supporting isolated EPs characterized by increased se…

quant-ph2018★ 1 cited

Winding around Non-Hermitian Singularities: General Theory and Topological Features

Qi Zhong, Mercedeh Khajavikhan, Demetrios Christodoulides +1

Non-Hermitian singularities are ubiquitous in non-conservative open systems. These singularities are often points of measure zero in the eigenspectrum of the system which make them…

quant-ph2018

Localization control of few-photon states in parity-symmetric photonic molecules under balanced pumping

C D B Bentley, A Celestino, A M Yacomotti +2

We theoretically investigate the problem of localization control of few-photon states in driven-dissipative parity-symmetric photonic molecules. We show that a quantum feedback loo…