We present the analysis of self-injection locking a single-frequency laser diode to high-Q whispering gallery mode (WGM) microresonator with Rayleigh backscattering. Simple analytical formulas for width band and resulting linewidth are derived.

Abstract The stabilization and manipulation of laser frequency by means an external cavity are nearly ubiquitously used in fundamental research applications. While most the light transmits through cavity, presence some back-scattered from to laser, self-injection locking effect can take place, which locks emission mode similar frequency. leads dramatic reduction linewidth noise. Using this approach, a common semiconductor locked ultrahigh- Q microresonator obtain sub-Hertz linewidth, on par...

Using the parity and time reversal symmetries of a two-dimensional spin-orbit coupled Bose-Einstein condensate in lattice created by Zeeman field, we identify find numerically various families localized solutions, including multipole half-vortex solitons. The obtained solutions may exist at any direction gauge field with respect to can be found either finite gaps (for repulsive interatomic interactions) or semi-infinite gap attractive interactions). existence half-vortices requires higher...

We predict the existence of a novel type flat-top dissipative solitonic pulses, "platicons", in microresonators with normal group velocity dispersion (GVD). propose methods to generate these platicons from cw pump. Their duration may be altered significantly by tuning pump frequency. The transformation discrete energy spectrum dark solitons Lugiato-Lefever equation into quasicontinuous is demonstrated. Generation similar structures also possible bi-harmonic, phase/amplitude modulated or via...

Optical whispering gallery mode (WGM) resonators allow combination of small volume with high Q-factor. Silicon is a major material for modern microelectronics and photonics. However, relatively low Q-factors optical Si microresonators demonstrated so far have limited some promising applications. We report what we believe first time measurement Q-factor 1.2×109 in millimeter scale crystalline silicon at 1550 nm wavelength. A novel hemispherical coupler allowed us to reach up 35% coupling efficiency.

We present a novel method allowing high-power single-frequency emission with sub-kHz linewidth from compact multi-frequency diode laser locked to high-Q optical microresonator. Using MgF2microresonator and operating at 1535 nm the output power of 100 mW an spectrum consisting approximately 50 lines MHz linewidth, we observed collapse single line or several mW. The Bogatov effect predicted more than 30 years ago was studied in laser. For analysis considered effect, original theoretical model...

Continuous-wave-driven Kerr nonlinear microresonators give rise to self-organization in terms of dissipative solitons, which constitute optical frequency combs that can be used generate low-noise microwave signals. Here, by applying either amplitude or phase modulation the driving laser we create an intracavity potential trap, discipline repetition rate solitons. We demonstrate this effect gives a novel spectral purification mechanism external signal frequency, leading reduced noise output...

We introduce the first-principle model describing frequency comb generation in a whispering-gallery-mode microresonator with backscattering-induced coupling between counterpropagating waves. The elaborated provides deep insights and an accurate description of complex dynamics nonlinear processes such systems. analyze backscattering impact on splitting reshaping resonances demonstrate modulational instability normal dispersion regime subsequent generation. present discuss features soliton...

Self-injection locking is a dynamic phenomenon representing stabilization of the emission frequency an oscillator with passive cavity enabling filtered coherent feedback to cavity. For instance, self-injection semiconductor laser high-quality-factor (high-Q) whispering gallery mode (WGM) microresonator can result in multiple orders magnitude reduction linewidth. The was broadly studied experiments, but its detailed theoretical model allowing improving performance does not exist. In this...

Abstract Soliton microcombs constitute chip-scale optical frequency combs, and have the potential to impact a myriad of applications from synthesis telecommunications astronomy. The demonstration soliton formation via self-injection locking pump laser microresonator has significantly relaxed requirement on external driving lasers. Yet date, nonlinear dynamics this process not been fully understood. Here, we develop an original theoretical model microresonator, i.e., locking, construct...

Dissipative Kerr solitons have paved the way to broadband and fully coherent optical frequency combs in microresonators. Here, we demonstrate numerically that slow tuning of pump laser conjunction with phase or amplitude modulation corresponding free spectral range microresonator, provides reliable convergence an initially excited chaotic comb state a single dissipative soliton (DKS) state. The efficiency this approach depends on both speed depth. relevance proposed method is confirmed...

We present the results of asymptotic and numerical analysis dissipative Kerr solitons in whispering gallery mode microresonators influenced by higher order dispersive terms leading to appearance a wave (Cherenkov radiation). Combining direct perturbation method with moments we find expressions for frequency, strength, spectral width soliton velocity. Mutual influence was studied. The formation leads shift spectrum maximum from pump frequency (spectral recoil), while displaces peak zero...

We studied the generation and dynamics of solitonic pulses, platicons, in microresonators at normal group velocity dispersion due to pump amplitude modulation. proposed that, if required frequency modulation is too large for available modulators, it possible use subharmonic phase platicon generation. It was also demonstrated that control repetition rate platicons by tuning frequency. The range found be much wider than bright solitons. influence high-order on properties. shown both...

We developed an original model describing the process of frequency comb generation in self-injection locking regime and performed numerical simulation this process.Generation dissipative Kerr solitons at anomalous group velocity dispersion was studied numerically. Different regimes soliton excitation depending on phase, backscattering parameter pump power were identified. It also proposed confirmed numerically that may provide easy way for combs normal dispersion. Generation platicons...

We demonstrate numerically novel mechanism providing generation of the flat-top solitonic pulses, platicons, in optical microresonators at normal GVD via negative thermal effects. found that platicon excitation is possible if ratio photon lifetime to relaxation time large enough. show there are two regimes depending on pump amplitude: smooth one and oscillatory one. Parameter ranges analysed for different values time, frequency-scan rate coefficient. Possibility turn-key regime also shown.

We discover that a spatially localized gain supports stable vortex solitons in media with cubic nonlinearity and two-photon absorption. The interplay between nonlinear losses amplifying rings results the suppression of otherwise ubiquitous azimuthal modulation instabilities radially symmetric solitons. find topology profile imposes restrictions on maximal possible charge Symmetry breaking occurs at high levels, resulting formation necklace composed asymmetric bright spots.

We demonstrate that flat-topped dissipative solitonic pulses, "platicons", and corresponding frequency combs can be excited in optical microresonators with normal group velocity dispersion using either the amplitude modulation of pump or bichromatic pump. Soft excitation may occur a particular range if depth is large enough close to free spectral microresonator.

We generalize the coupled mode formalism to study generation of frequency combs in microresonators with simultaneous Raman and Kerr nonlinearities investigate an impact former on formation dynamics platicons regime normal group velocity dispersion. demonstrate that effect initiates sidebands, which cascade further four-wave mixing reshape into Raman-Kerr combs. reveal scattering induces a strong instability platicon pulses associated This results branching complex spatiotemporal dynamics.

Summary form only given. The formation of dissipative Kerr solitons in optical microresonators enables fully coherent frequency combs with microwave repetition rates. Of particular interest is the single soliton state that exhibits a spectrally smooth sech <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> profile imperative for applications such as communications, receivers and dual-comb spectroscopy. However, generation process comb...

We introduce a mechanism to stabilize spatiotemporal solitons in Kerr nonlinear media, based on the dispersion of linear coupling between field components forming soliton states. Specifically, we consider two-core guiding structure with inter-core (CD). show that CD profoundly affects properties solitons, causing complete stabilization otherwise highly unstable media focusing nonlinearity. also find presence stimulates formation bound states, which however are unstable.

Self-injection locking to a high-quality-factor microresonator is key component of various up-to-date photonic applications, including compact narrow-linewidth lasers and microcomb sources. For optimal construction such devices it necessary know the parameters mode, which challenging task. We developed verified experimentally an original technique based on fundamentals self-injection effect, allows determining mode (quality factor, vertical index) as well laser diode parameters. demonstrated...

High-quality-factor optical microresonators have become an appealing object for numerous applications. However, the mid-infrared band experiences a lack of applicable materials nonlinear photonics. Crystalline germanium demonstrates attractive material properties such as high refractive index, large transparency window including mid-IR band, particularly long wave multiphonon absorption limit. Nevertheless, reported losses in might not allow potential Ge-based devices to be revealed. In this...

We uncover that, in contrast to the common belief, stable dissipative solitons exist media with uniform gain presence of nonuniform cubic losses, whose local strength grows coordinate η (in one dimension) faster than |η|. The spatially-inhomogeneous absorption also supports new types solitons, that do not media. In particular, single-well profiles give rise spontaneous symmetry breaking fundamental focusing nonlinearity, while dipoles are supported by double-well landscapes. Dipole feature...