# Demonstration of a two-dimensional PT-symmetric crystal: Bulk dynamics, topology, and edge states

@article{Kremer2018DemonstrationOA, title={Demonstration of a two-dimensional PT-symmetric crystal: Bulk dynamics, topology, and edge states}, author={Mark Kremer and Tobias Biesenthal and Matthias Heinrich and Ronny Thomale and Alexander Szameit}, journal={arXiv: Optics}, year={2018} }

In 1998, Carl Bender challenged the perceived wisdom of quantum mechanics that the Hamiltonian operator describing any quantum mechanical system has to be Hermitian. He showed that Hamiltonians that are invariant under combined parity-time (PT) symmetry transformations likewise can exhibit real eigenvalue spectra. These findings had a particularly profound impact in the field of photonics, where PT-symmetric potential landscapes can be implemented by appropriately distributing gain and loss…

## 17 Citations

Experimental Realisation of PT-Symmetric Flat Bands

- Physics2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)
- 2019

Non-Hermitian physics, and in particular its well-known representative of PT-symmetry, is a field of great interest in current research. Photonics allows for the implementation of its associated…

Realization of photonic charge-2 Dirac point by engineering super-modes in topological superlattices

- Physics
- 2019

Quite recently, an unconventional variety of fourfold linear band degeneracy points has been discovered in certain condensed-matter systems. Contrary to standard 3-D Dirac monopoles, these quadruple…

Polariton condensation into vortex states in the synthetic magnetic field of a strained honeycomb lattice

- PhysicsSciPost Physics
- 2022

Photonic materials are a rapidly growing platform for studying condensed matter physics with light, where the exquisite control capability is allowing us to learn about the relation between…

Efficient Light Funneling based on the non-Hermitian Skin Effect

- Physics
- 2020

In the last two decades, the ubiquitous effect of dissipation has proven to entail astonishing non-Hermitian features, rather than just being an inescapable nuisance. As an alternative route to…

Unambiguous scattering matrix for non-Hermitian systems

- PhysicsPhysical Review A
- 2020

$\mathcal{PT}$ symmetry is a unique platform for light manipulation and versatile use in unidirectional invisibility, lasing, sensing, etc. Broken and unbroken $\mathcal{PT}$-symmetric states in…

Lattice Resonances in Optical Metasurfaces With Gain and Loss

- PhysicsProceedings of the IEEE
- 2020

The effects of parity-time (PT) symmetry breaking in active-lossy plasmonic arrays are demonstrated: the emergence of exceptional points, nontrivial topology of photonic bands, diverging effective unit-cell polarizability, and spin polarization in the PT-broken phase.

PHYSICAL REVIEW B 102, 155303 (2020) Modal Purcell factor in PT -symmetric waveguides

- Physics
- 2020

We study the spontaneous emission rate of a dipole emitter in PT -symmetric environment of two coupled waveguides using the reciprocity approach generalized to nonorthogonal eigenmodes of…

Roadmap on topological photonics

- PhysicsJournal of Physics: Photonics
- 2022

Topological photonics seeks to control the behaviour of the light through the design of protected topological modes in photonic structures. While this approach originated from studying the…

Quadratic pseudospectrum for identifying localized states

- Computer Science, Mathematics
- 2022

It is proved that the quadratic pseudospectrum is local, and the bounds on the errors that are incurred by truncating the system in the vicinity of where the pseudospects are being calculated are derived.

Quasibound states in the continuum induced by
PT
symmetry breaking

- PhysicsPhysical Review B
- 2021

Denis V. Novitsky1,∗ Alexander S. Shalin2,3,4, Dmitrii Redka5,4, Vjaceslavs Bobrovs, and Andrey V. Novitsky6,2 B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus,…

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