Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userCharacterizing pump line phase offset of a single-soliton Kerr comb by dual comb interferometry
92
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We experimentally demonstrate phase retrieval of a single-soliton Kerr comb using electric field cross-correlation implemented via dual-comb interferometry. The phase profile of the Kerr comb is acquired through the heterodyne beat between the Kerr comb and a reference electro-optical comb with a pre-characterized phase profile. The soliton Kerr comb has a nearly flat phase profile, and the pump line is observed to show a phase offset which depends on the pumping parameters. The experimental results are in agreement with numerical simulations. Our all-linear approach enables rapid measurements (3.2 $mu$s) with low input power (20 $mu$W).
rate research
Read More
Dissipative Kerr cavity solitons (DKSs) are localized particle-like wave packets that have attracted peoples great interests in the past decades. Besides being an excellent candidate for studying nonlinear physics, DKSs can also enable the generation of broadband frequency combs which have revolutionized a wide range of applications. The formation of DKSs are generally explained by a double balance mechanism. The group velocity dispersion is balanced by the Kerr effect; and the cavity loss is compensated by the parametric gain. Here, we show that DKSs can emerge through the interplay between dispersive loss and Kerr gain, without the participation of group velocity dispersion. By incorporating rectangular gate spectral filtering in a zero-dispersion coherently driven Kerr cavity, we demonstrate the generation of Nyquist-pulse-like solitons with unprecedented ultra-flat spectra in the frequency domain. The discovery of pure dissipation enabled solitons reveals new insights into the cavity soliton dynamics, and provides a useful tool for spectral tailoring of Kerr frequency combs.
Fast-responding detector arrays are commonly used for imaging rapidly-changing scenes. Besides array detectors, a single-pixel detector combined with a broadband optical spectrum can also be used for rapid imaging by mapping the spectrum into a spatial coordinate grid and then rapidly measuring the spectrum. Here, optical frequency combs generated from high-$Q$ silica microresonators are used to implement this method. The microcomb is dispersed in two spatial dimensions to measure a test target. The target-encoded spectrum is then measured by multi-heterodyne beating with another microcomb having a slightly different repetition rate, enabling an imaging frame rate up to 200 kHz and fillrates as high as 48 MegaPixels/s. The system is used to monitor the flow of microparticles in a fluid cell. Microcombs in combination with a monolithic waveguide grating array imager could greatly magnify these results by combining the spatial parallelism of detector arrays with spectral parallelism of optics.
Kerr soliton frequency comb generation in monolithic microresonators recently attracted great interests as it enables chip-scale few-cycle pulse generation at microwave rates with smooth octave-spanning spectra for self-referencing. Such versatile platform finds significant applications in dual-comb spectroscopy, low-noise optical frequency synthesis, coherent communication systems, etc. However, it still remains challenging to straightforwardly and deterministically generate and sustain the single-soliton state in microresonators. In this paper, we propose and theoretically demonstrate the excitation of single-soliton Kerr frequency comb by seeding the continuous-wave driven nonlinear microcavity with a pulsed trigger. Unlike the mostly adopted frequency tuning scheme reported so far, we show that an energetic single shot pulse can trigger the single-soliton state deterministically without experiencing any unstable or chaotic states. Neither the pump frequency nor the cavity resonance is required to be tuned. The generated mode-locked single-soliton Kerr comb is robust and insensitive to perturbations. Even when the thermal effect induced by the absorption of the intracavity light is taken into account, the proposed single pulse trigger approach remains valid without requiring any thermal compensation means.
Optical frequency comb (OFC) technology has been the cornerstone for scientific breakthroughs such as precision frequency metrology, redefinition of time, extreme light-matter interaction, and attosecond sciences. While the current mode-locked laser-based OFC has had great success in extending the scientific frontier, its use in real-world applications beyond the laboratory setting remains an unsolved challenge. Microresonator-based OFCs, or Kerr frequency comb, have recently emerged as a candidate solution to the challenge because of their preferable size, weight, and power consumption (SWaP). On the other hand, the current phase stabilization technology requires either external optical references or power-demanding nonlinear processes, overturning the SWaP benefit of Kerr frequency combs. Introducing a new concept in phase control, here we report an internally phase stabilized Kerr frequency comb without the need of any optical references or nonlinear processes. We describe the comb generation analytically with the theory of cavity induced modulation instability, and demonstrate for the first time that the optical frequency can be stabilized by control of two internally accessible parameters: an intrinsic comb offset and the comb spacing. Both parameters are phase locked to microwave references, with 55 mrad and 20 mrad residual phase noises, and the resulting comb-to-comb frequency uncertainty is 0.08 Hz or less. Out-of-loop measurements confirm good coherence and stability across the comb, with measured optical frequency fractional instabilities of 5x10^-11/sqrt(t). The new phase stabilization method preserves the Kerr frequency combs key advantages and potential for chip-scale electronic and photonic integration.
75 -
Philippe Guay
, Alex Tourigny-Plante
, Vincent Michaud-Belleau andn Nicolas Bourbeau Hebert
2021
The impact of photodetector nonlinearity on dual-comb spectrometers is described and compared to that of Michelson-based Fourier transform spectrometers (FTS). The optical sampling occurring in the dual-comb approach, being the key difference with FTS, causes optical aliasing of the nonlinear spectral artifacts. Measured linear and nonlinear interferograms are presented to validate the model. Absorption lines of H$^{13}$CN are provided to understand the impact of nonlinearity on spectroscopic measurements.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
