Controlling lasing around Exceptional Points in Coupled Nanolasers

Abstract

Coupled nanolasers are of growing interest for on-chip optical computation and data transmission, which requires an understanding of how lasers interact to form complex systems. The non-Hermitian interaction between two coupled resonators, when excited selectively, can lead to parity-time symmetry, the formation of exceptional points, and subsequently spectral control and increased sensitivity. These investigations have been limited to pump energies close to the lasing threshold, and large or narrow-line lasers. Here, by programmable optical excitation we study two coupled nanolasers significantly above threshold, where mode instability plays an important role. We map the mode evolution around two exceptional points, and observe lasing gaps due to reversed pump dependence which compare well with nonlinear theory. Finally, the coupling can be exploited to control the lasing threshold and wavelength, and for frequency switching around the lasing gap. Controlled and integrated nanolasers constitutes a promising platform for future highly sensitive and programmable on-chip laser sources.

arXiv comment8 pages, 4 figures

References in corpus (16)

• Real Spectra in Non-Hermitian Hamiltonians Having PT Symmetry
• Deep Learning with Coherent Nanophotonic Circuits
• Nonreciprocal light transmission in parity-time-symmetric whispering-gallery microcavities
• Loss-induced suppression and revival of lasing
• Reversing the Pump-Dependence of a Laser at an Exceptional Point
• Pump-induced Exceptional Points in Lasers
• Sensing with exceptional surfaces: combining sensitivity with robustness
• Spontaneous mirror-symmetry breaking in a photonic molecule
• Direct generation of tunable orbital angular momentum beams in microring lasers with broadband exceptional points
• Room temperature electrically pumped topological insulator lasers
• High-precision spectral tuning of micro and nanophotonic cavities by resonantly enhanced photoelectrochemical etching
• Complex active optical networks as a new laser concept
• Wurtzite InP Microdisks: from Epitaxy to Room-Temperature Lasing
• Nonlinear exceptional-point lasing with ab-initio Maxwell-Bloch theory
• Sensitivity and spectral control of network lasers
• Image classification using collective optical modes of an array of nanolasers

Cited by in corpus (4)

• Mode visualisation and control of complex lasers using neural networks
• Single-mode emission by phase-delayed coupling between nano-lasers
• Chiral lasing via broken parity-time symmetry in bound-state-in-the-continuum metasurfaces
• Supercharging exceptional points: Full-spectrum pairwise coalescence in non-Hermitian systems