skip to main content

Title: Monostable dissipative Kerr solitons

Kerr microcombs hold the promise of bringing frequency combs onto the chip and into a variety of applications requiring low size, weight, power, and cost. However, reliable Kerr microcomb generation is hindered by the thermal effect and multistability of dissipative Kerr solitons (DKSs). Past approaches toward Kerr microcomb reliability include either deterministic single-soliton generation or self-starting soliton behavior but not both. Here we describe a regime of DKSs that isbothdeterministic and self-starting, in which only a single soliton can stably exist. We term this new DKS regime “monostable DKSs” (MS-DKSs) as all other optical behaviors, such as continuous-wave-only and multiple solitons, are fundamentally forbidden by the design. We establish a graphical model to describe MS-DKSs and discuss the design principles of MS-DKSs. We numerically demonstrate the MS-DKS behavior in an example periodically poled lithium niobate microring resonator.

more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 122
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Pumped Kerr microresonators have recently emerged as a promising source of optical frequency combs. The production of octave-spanning spectrum by dispersive waves and consequent demonstration of carrier-envelope phase locking has paved the way toward a wide fi eld of comb applications. Nevertheless, there remain some obstacles before the goal of a simple off-the-shelf comb source is achieved. Current microcomb implementations rely on cavity solitons, and several of the present limitations of microcombs are tied to those of soliton waveforms. Cavity solitons exist only in a small red-detuned region of the pump parameters, where waveforms suffer from thermal instabilities. Furthermore, solitons are always obtained in the multistable regime, and therefore cannot be continuously connected to cw, so that elaborate, often non-deterministic, access protocols are needed to produce them. Another issue is that because solitons are accompanied by a strong pedestal, their comb power efficiency is low. 
    more » « less
  2. Microresonator-based soliton generation promises chip-scale integration of optical frequency combs for applications spanning from time keeping to frequency synthesis. Access to the soliton repetition rate is a prerequisite for those applications. While miniaturized cavities harness Kerr nonlinearity and enable terahertz soliton repetition rates, such high rates are not amenable to direct electronic detection. Here, we demonstrate hybrid Kerr and electro-optic microcombs using a lithium niobate thin film that exhibits both Kerr and Pockels nonlinearities. By interleaving the high-repetition-rate Kerr soliton comb with the low-repetition-rate electro-optic comb on the same waveguide, wide Kerr soliton mode spacing is divided within a single chip, allowing for direct electronic detection and feedback control of the soliton repetition rate. Our work establishes an integrated approach to electronically access terahertz solitons, paving the way for building chip-scale referenced comb sources.

    more » « less
  3. Abstract

    Dissipative Kerr soliton (DKS) microcomb has emerged as an enabling technology that revolutionizes a wide range of applications in both basic science and technological innovation. Reliable turnkey operation with sub-optical-cycle and sub-femtosecond timing jitter is key to the success of many intriguing microcomb applications at the intersection of ultrafast optics and microwave electronics. Here we propose an approach and demonstrate the first turnkey Brillouin-DKS frequency comb to the best of our knowledge. Our microresonator-filtered laser design offers essential benefits, including phase insensitivity, self-healing capability, deterministic selection of the DKS state, and access to the ultralow noise comb state. The demonstrated turnkey Brillouin-DKS frequency comb achieves a fundamental comb linewidth of 100 mHz and DKS timing jitter of 1 femtosecond for averaging times up to 56 μs. The approach is universal and generalizable to various device platforms for user-friendly and field-deployable comb devices.

    more » « less
  4. Abstract

    Dissipative Kerr solitons in resonant frequency combs offer a promising route for ultrafast mode-locking, precision spectroscopy and time-frequency standards. The dynamics for the dissipative soliton generation, however, are intrinsically intertwined with thermal nonlinearities, limiting the soliton generation parameter map and statistical success probabilities of the solitary state. Here, via use of an auxiliary laser heating approach to suppress thermal dragging dynamics in dissipative soliton comb formation, we demonstrate stable Kerr soliton singlet formation and soliton bursts. First, we access a new soliton existence range with an inverse-sloped Kerr soliton evolution—diminishing soliton energy with increasing pump detuning. Second, we achieve deterministic transitions from Turing-like comb patterns directly into the dissipative Kerr soliton singlet pulse bypassing the chaotic states. This is achieved by avoiding subcomb overlaps at lower pump power, with near-identical singlet soliton comb generation over twenty instances. Third, with the red-detuned pump entrance route enabled, we uncover unique spontaneous soliton bursts in the direct formation of low-noise optical frequency combs from continuum background noise. The burst dynamics are due to the rapid entry and mutual attraction of the pump laser into the cavity mode, aided by the auxiliary laser and matching well with our numerical simulations. Enabled by the auxiliary-assisted frequency comb dynamics, we demonstrate an application of automatic soliton comb recovery and long-term stabilization against strong external perturbations. Our findings hold potential to expand the parameter space for ultrafast nonlinear dynamics and precision optical frequency comb stabilization.

    more » « less
  5. Abstract

    The advantages of low cost, compact size, and reduced power consumption makes a photonic chip‐based ultrafast laser source an appealing technology for diverse applications such as all‐optical signal processing, frequency metrology, spectroscopy, and sensing. To date, on‐chip ultrafast sources are typically generated by microresonator‐based Kerr‐comb solitons, which require precise phase tuning and frequency agile lasers to access the soliton state. Here, this work reports the first experimental demonstration of an externally pumped on‐chip ultrafast soliton laser source based on Raman soliton self‐frequency shift. By capitalizing on strong optical nonlinearity and versatile dispersion control in Ge28Sb12Se60chalcogenide glass waveguides, 185 fs duration Raman soliton generation has been demonstrated, possessing continuous wavelength tunability from 1589 to 1807 nm with signal‐to‐noise ratios consistently exceeding 65 dB. The source operates with pump pulse energies as low as 1.08 pJ, representing over three orders of magnitude improvement compared to fiber‐based Raman soliton sources. In addition, the generated solitons exhibit excellent spectral purity and stability free from parasitic sidebands. These experimental results are further validated by theoretical analysis, revealing insights into the soliton dynamics and critical device design guidelines. This work therefore enables a new class of broadly tunable, energy‐efficient, compact, and potentially cost‐effective on‐chip ultrafast laser sources.

    more » « less