# Topological Defect Engineering and PT Symmetry in Non-Hermitian Electrical Circuits.

@article{Stegmaier2021TopologicalDE, title={Topological Defect Engineering and PT Symmetry in Non-Hermitian Electrical Circuits.}, author={Alexander Stegmaier and Stefan Imhof and Tobias Helbig and Tobias Hofmann and Ching Hua Lee and Mark Kremer and Alexander Fritzsche and Thorsten Feichtner and Sebastian Klembt and S. Hofling and Igor Boettcher and Ion Cosma Fulga and Oliver G. Schmidt and Martin Greiter and Tobias Kie{\ss}ling and Alexander Szameit and Ronny Thomale}, journal={Physical review letters}, year={2021}, volume={126 21}, pages={ 215302 } }

We employ electric circuit networks to study topological states of matter in non-Hermitian systems enriched by parity-time symmetry PT and chiral symmetry anti-PT (APT). The topological structure manifests itself in the complex admittance bands which yields excellent measurability and signal to noise ratio. We analyze the impact of PT-symmetric gain and loss on localized edge and defect states in a non-Hermitian Su-Schrieffer-Heeger (SSH) circuit. We realize all three symmetry phases of the…

## 26 Citations

Edge state mimicking topological behavior in a one-dimensional electrical circuit

- PhysicsNew Journal of Physics
- 2021

For one-dimensional (1D) topological insulators, the edge states always reside in the bulk bandgaps as isolated modes. The emergence and vanishing of these topological edge states are always…

Constant intensity discrete diffraction in anti-PT-symmetric electric circuits

- PhysicsResults in Physics
- 2021

Unveiling Topological Charges and Their Manipulation in Electronic Circuits

- Materials Science
- 2022

Leveraging topological properties in the response of electromagnetic systems can greatly enhance their potential. Although the investigation of singularity-based electromagnetics and non-Hermitian…

Inner Skin Effects on Non-Hermitian Topological Fractals

- Physics
- 2022

Non-Hermitian (NH) crystals, quasicrystals and amorphous network with only open boundary condition feature skin effect, displaying accumulation of a macroscopic number of states near one of its…

Designing non-Hermitian real spectra
through electrostatics

- PhysicsScience Bulletin
- 2022

Non-hermiticity presents a vast newly opened territory that harbors new physics and applications such as lasing and sensing. However, only non-Hermitian systems with real eigenenergies are
stable,…

Multiple crossed non-Hermitian Su-Schrieffer-Heeger chains coupled via a mutual defect site

- Physics
- 2022

We analyze topological systems with dimensions larger than one, comprised of several one-dimensional Su-SchriefferHeeger (SSH) lattices coupled through a single defect. The defect induces edges…

Room-Temperature Topological Polariton Laser in an Organic Lattice.

- PhysicsNano letters
- 2021

This communication demonstrates exciton-polariton lasing for topological defects emerging from the imprinted lattice structure at room temperature, using red fluorescent protein derived from DsRed of Discosoma sea anemones and a patterned mirror cavity to tune the lattice potential landscape of a linear Su-Schrieffer-Heeger chain.

Non-Hermitian Squeezed Polarons

- Physics
- 2022

Recent experimental breakthroughs in non-Hermitian ultracold atomic lattices have dangled tantalizing prospects in realizing exotic, hitherto unreported many-body non-Hermitian quantum phenomena. In…

Linear Response for pseudo-Hermitian Hamiltonian Systems: Application to PT-Symmetric Qubits

- Physics
- 2022

Motivated by the recent advances in modelling the pseudo-Hermitian Hamiltonian (pHH) systems using superconducting qubits we analyze their quantum dynamics subject to a small time-dependent…

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