Parity–time symmetry and exceptional points in photonics

Özdemir, Şahin Kaya; Rotter, Stefan; Nori, Franco; Yang, Lan

doi:10.1038/s41563-019-0304-9

Cited by 1,199 publications

(758 citation statements)

References 122 publications

Supporting

Mentioning

756

Contrasting

Order By: Relevance

“…Because the neuron is an open system interacting with the extracellular region, an open system in non-Hermitian photonics [18][19][20] is a suitable platform for realizing photonic neurons. Because the neuron is an open system interacting with the extracellular region, an open system in non-Hermitian photonics [18][19][20] is a suitable platform for realizing photonic neurons.…”

Section: Analogy Of a Neuron In Nonlinear Photonic Systemsmentioning

confidence: 99%

“…The study of state-dependent channels in wave systems is readily found in traditional photonic devices, such as laser with gain saturation [12] and mode locking [13] with saturable absorption. [17] Non-Hermitian photonics [18][19][20] inspired by parity-time (PT) symmetry [21] has rejuvenated the utilization of nonlinear wave channels for photonic [22][23][24] or microwave [25] functionalities. [17] Non-Hermitian photonics [18][19][20] inspired by parity-time (PT) symmetry [21] has rejuvenated the utilization of nonlinear wave channels for photonic [22][23][24] or microwave [25] functionalities.…”

mentioning

confidence: 99%

“…[17] Non-Hermitian photonics [18][19][20] inspired by parity-time (PT) symmetry [21] has rejuvenated the utilization of nonlinear wave channels for photonic [22][23][24] or microwave [25] functionalities. Early studies have mostly focused on linear wave phenomena near the exceptional point (EP), [20,26] such as asymmetric [27] and sensitive [28] excitations, unidirectional invisibility, [29] enhanced spin, [30,31] or orbital angular momentum, [32] and asymmetric modal conversion, [33] which have been demonstrated in waveguides, [27,33] fibers, [29] metamaterials, [30,31] and resonators. Due to the design flexibility of photonic platforms and the Schrödingerlike paraxial wave equation for light, photonic structures have been employed as a testbed for examining wave phenomena in PT-symmetric systems.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Neuromorphic Functions of Light in Parity‐Time‐Symmetric Systems

Piao

Park

2019

Advanced Science

View full text Add to dashboard Cite

As an elementary processor of neural networks, a neuron performs exotic dynamic functions, such as bifurcation, repetitive firing, and oscillation quenching. To achieve ultrafast neuromorphic signal processing, the realization of photonic equivalents to neuronal dynamic functions has attracted considerable attention. However, despite the nonconservative nature of neurons due to energy exchange between intra‐ and extra‐cellular regions through ion channels, the critical role of non‐Hermitian physics in the photonic analogy of a neuron has been neglected. Here, a neuromorphic non‐Hermitian photonic system ruled by parity‐time symmetry is presented. For a photonic platform that induces the competition between saturable gain and loss channels, dynamical phases are classified with respect to parity‐time symmetry and stability. In each phase, unique oscillation quenching functions and nonreciprocal oscillations of light fields are revealed as photonic equivalents of neuronal dynamic functions. The proposed photonic system for neuronal functionalities will become a fundamental building block for light‐based neural signal processing.

show abstract

Section: Analogy Of a Neuron In Nonlinear Photonic Systemsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Neuromorphic Functions of Light in Parity‐Time‐Symmetric Systems

Piao

Park

2019

Advanced Science

View full text Add to dashboard Cite

show abstract

“…The non‐Hermitian system, whose energy conservation no longer holds, is another exciting topic in the frontier . Because of the broken symmetries, many non‐trivial behaviors can be found in the system, such as unidirectional invisibility, topological energy transfer, and sensing enhancement.…”

Section: Introductionmentioning

confidence: 99%

Prethermalization and Nonreciprocal Phonon Transport in a Levitated Optomechanical Array

Liu

Yin

2020

Adv Quantum Tech

View full text Add to dashboard Cite

Recent advances in levitated optomechanics have brought new opportunities for the study of macroscopic quantum mechanics and precision measurement. Previous studies have mainly focused on the single levitated nanoparticle, the systems of multiple levitated nanoparticles were rarely involved. Here an array of optically levitated nanospheres in vacuum is considered and nontrivial phonon transport in this system is investigated. The levitated nanospheres are coupled by optical binding. Key parameters of this system, such as the interaction range, trapping frequencies, and mechanical dissipation, are highly tunable. Due to these advantages, counter‐intuitive phenomena such as prethermalization and nonreciprocal phonon transport can be achieved by tuning the spacing between neighboring spheres, the mechanical dissipation, and the trapping frequency of each sphere. The system provides a great platform to investigate novel phonon transport and thermal energy transfer.

show abstract

“…Non‐reciprocal optical devices such as the optical isolators and circulators are important in the development of photonic integrated circuits . The conventional non‐reciprocal optical devices are based on Faraday effect via an externally applied magnetic field in the direction of the propagation.…”

Section: Introductionmentioning

confidence: 99%

Non‐Reciprocity in High‐Q Ferromagnetic Microspheres via Photonic Spin–Orbit Coupling

Chai

Zhao

Tang

et al. 2019

Laser & Photonics Reviews

View full text Add to dashboard Cite

Non‐reciprocal devices serving as fundamental elements in photonic and microwave circuits have attracted great attention for its applications in both classical and quantum information processing. The spin–orbit coupling (SOC) of light in microstructures shows that the polarization affects and controls the spatial degrees of freedom of light, which could been exploited to break the reciprocity of light transmission. Here, non‐reciprocal light transmission is demonstrated experimentally in high‐quality factor yttrium iron garnet microspheres via photonic SOC and Faraday effect. By applying an magnetic field in the vertical direction of resonator equator, the degeneracy of the clockwise and counter‐clockwise whispering gallery modes are lifted. The non‐reciprocal effect is shown for both polarizations and promises applications including non‐reciprocal photonic devices, magneto‐optic modulators, and magnetometers.

show abstract

Parity–time symmetry and exceptional points in photonics

Cited by 1,199 publications

References 122 publications

Neuromorphic Functions of Light in Parity‐Time‐Symmetric Systems

Neuromorphic Functions of Light in Parity‐Time‐Symmetric Systems

Prethermalization and Nonreciprocal Phonon Transport in a Levitated Optomechanical Array

Non‐Reciprocity in High‐Q Ferromagnetic Microspheres via Photonic Spin–Orbit Coupling

Contact Info

Product

Resources

About