Related papers: Unidirectional mode selection in bistable quantum …
Ring lasers exhibit rich operational regimes such as unidirectional, bidirectional, or bistable operation. The two-mode dynamics of the counter-propagating modes - clockwise (CW) and counterclockwise (CCW) and their selection, have gained…
Rapid development of Fabry-Perot quantum cascade laser frequency combs has converted them from laboratory devices to key components of next-generation fast molecular spectrometers. Recently, free-running ring quantum cascade lasers allowed…
We develop a general formalism to study laser operation in active micro-ring resonators supporting two counterpropagating modes. Our formalism is based on the coupled-mode equations of motion for the field amplitudes in the two…
Ring quantum cascade lasers (QCLs) proved to be a versatile tool for generating tunable and stable frequency combs in the mid infrared range in the form of quantum walk combs. By homogeneously integrating a racetrack QCL with a passive…
Ring quantum cascade lasers have recently gained considerable attention, showing ultrastable frequency comb and soliton operation, thus opening a way to integrated spectrometers in the midinfrared and terahertz fingerprint regions. Thanks…
We experimentally and theoretically study the characteristics of semiconductor ring lasers bidirectionally coupled by a single bus waveguide. This configuration has, e.g., been suggested for use as an optical memory and as an optical neural…
Using the effective mass and rectangular potential approximations, the theory of electron dynamic conductivity is developed for the plane multilayer resonance tunnel structure placed into a constant electric field within the model of open…
We show that a topological investigation of the phase space of a Semiconductor Ring Laser can be used to devise switching schemes which are alternative to optical pulse injection of counter-propagating light. To provide physical insight in…
Semiconductor ring lasers are miniaturized devices that operate on clockwise and counterclockwise modes. These modes are not coupled in the absence of intracavity reflectors, which prevents the formation of a standing wave in the cavity…
Unidirectional reflectionlessness is investigated in a waveguide quantum electrodynamics system that consists of a cavity and a $\Lambda$-type three-level quantum dot coupled to a one-dimensional plasmonic waveguide. Analytical expressions…
We introduce a class of unidirectional lasing modes associated with the frozen mode regime of non-reciprocal slow-wave structures. Such asymmetric modes can only exist in cavities with broken time-reversal and space inversion symmetries.…
Unidirectional optical systems enable selective control of light through asymmetric processing of radiation, effectively transmitting light in one direction while blocking unwanted propagation in the opposite direction. Here, we introduce a…
We demonstrate lasing into counter-propagating modes of a ring cavity using a gas of cold atoms as a gain medium. The laser operates under the usual conditions of magneto-optical trapping with no additional fields. We characterize the…
Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and…
Circular microresonators are micron sized dielectric disks embedded in material of lower refractive index. They possess modes of extremely high Q-factors (low lasing thresholds) which makes them ideal candidates for the realization of…
A theoretical and experimental investigation of the effects of mode coupling in a resonant macro- scopic quantum device is achieved in the case of a ring laser. In particular, we show both analytically and experimentally that such a device…
We studied theoretically coherent phenomena in the multimode dynamics of single section semiconductor ring lasers with Quantum Dots (QDs) active region. In the unidirectional ring configuration our simulations show the occurrence of…
We design coupled optical microcavities and report directional light emission from high-$Q$ modes for a broad range of refractive indices. The system consists of a circular cavity that provides a high-$Q$ mode in form of a whispering…
Electrically independent terahertz (THz) quantum cascade lasers (QCLs) are optically coupled in a Y configuration. Dual frequency, electronically switchable emission is achieved in one QCL using an aperiodic grating, designed using…
Imperfections in the surface of intracavity elements of an optical ring resonator can scatter light from one mode into the counterpropagating mode. The phase-locking of the cavity modes induced by this backscattering is a well-known example…