Alexey Tikan | EPFL Graph Search

I obtained my undergraduate degree in the framework of a joint program between Novosibirsk State University and École Polytechnique Paris and later completed PhD in the group of Prof. Pierre Suret and Prof. Stéphane Randoux at Laboratoire de Physique des Lasers, Atomes et Molécules (Lille, France). My research subject was related to the novel field of Integrable Turbulence that studies the dynamics of random waves in integrable nonlinear models. Experimentally, I have contributed to the development of a tool for single-shot detection of ultrafast optical fields which is considered until today to be the state-of-the-art. Upon joining the Laboratory of Photonics and Quantum Measurements at EPFL, I contribute to a project dedicated to the study of lattices of strongly coupled high-Q optical resonators.

Dissipative Solitons and Switching Waves in Dispersion-Modulated Kerr Cavities

Miles Henry Anderson, Alisa Davydova, Tobias Kippenberg, Alexey Tikan, Aleksandr Tusnin, Rui Ning Wang

We theoretically and experimentally investigate the formation of dissipative coherent structures in Kerr nonlinear optical microresonators, whose spectrum encompasses an integrated dispersion that exceeds the cavity free-spectral range. We are able to access this regime in low-dispersion photonic chip-based microresonators by employing synchronous pulse driving, which increases the peak power over the continuous-wave-driving regime. Exploring this dispersion-folded regime, we demonstrate that the presence of periodically varying dispersion can excite higher-order comb structures, which we explore in both the normal and anomalous dispersion regimes. In the former, we observe the coexistence of switching wave fronts with Faraday instability-induced period-doubling patterns. They manifest as strong satellite microcombs highly separated either side of the core microcomb, at an offset close to half the repetition rate but while sharing the same repetition rate. In the latter, for dissipative Kerr solitons in anomalous dispersion, we observe the formation of higher-order phase-matched dispersive waves ("Kelly -like" sidebands), where the folded dispersion crosses the frequency comb grid. We observe up to the fifth higher-order dispersive wave in our experiments and show that these higher-order dispersive waves coherently extend the soliton frequency comb bandwidth significantly. For both cases, we show that our results can be understood by considering four-wave mixing in a two-dimensional Fourier transform representation. The results demonstrate the rich novel nonlinear dynamics of driven dissipative nonlinear cavities with periodically varying dispersion in the dispersion-folded pumping regime.

AMER PHYSICAL SOC2023

Protected generation of dissipative Kerr solitons in supermodes of coupled optical microresonators

Mikhail Churaev, Xinru Ji, Tobias Kippenberg, Junqiu Liu, Alexey Tikan, Aleksandr Tusnin, Rui Ning Wang

A photonic dimer composed of two evanescently coupled high-Q microresonators is a fundamental element of multimode soliton lattices. It has demonstrated a variety of emergent nonlinear phenomena, including supermode soliton generation and soliton hopping. Here, we present another aspect of dissipative soliton generation in coupled resonators, revealing the advantages of this system over conventional single-resonator platforms. Namely, we show that the accessibility of solitons markedly varies for symmetric and antisymmetric supermode families. Linear measurements reveal that the coupling between transverse modes, giving rise to avoided mode crossings, can be substantially suppressed. We explain the origin of this phenomenon and show its influence on the dissipative Kerr soliton generation in lattices of coupled resonators of any type. Choosing an example of the topological Su-Schrieffer-Heeger model, we demonstrate how the edge state can be protected from the interaction with higher--order modes, allowing for the formation of topological Kerr solitons.

AMER ASSOC ADVANCEMENT SCIENCE2022

Zero dispersion Kerr solitons in optical microresonators

Miles Henry Anderson, Tobias Kippenberg, Junqiu Liu, Alexey Tikan, Wenle Weng

Solitons are shape preserving waveforms that are ubiquitous across nonlinear dynamical systems from BEC to hydrodynamics, and fall into two separate classes: bright solitons existing in anomalous group velocity dispersion, and switching waves forming 'dark solitons' in normal dispersion. Bright solitons in particular have been relevant to chip-scale microresonator frequency combs, used in applications across communications, metrology, and spectroscopy. Both have been studied, yet the existence of a structure between this dichotomy has only been theoretically predicted. We report the observation of dissipative structures embodying a hybrid between switching waves and dissipative solitons, existing in the regime of vanishing group velocity dispersion where third-order dispersion is dominant, hence termed as 'zero-dispersion solitons'. They are observed to arise from the interlocking of two modulated switching waves, forming a stable solitary structure consisting of a quantized number of peaks. The switching waves form directly via synchronous pulse-driving of a Si3N4 microresonator. The resulting comb spectrum spans 136 THz or 97% of an octave, further enhanced by higher-order dispersive wave formation. This dissipative structure expands the domain of Kerr cavity physics to the regime near to zero-dispersion and could present a superior alternative to conventional solitons for broadband comb generation. Here, the authors find the missing link for soliton microcombs that exist at the boundary where the group velocity dispersion of light changes sign: zero-dispersion solitons. The resulting microresonator frequency comb, based in Si3N4, spans almost an octave.

NATURE PORTFOLIO2022