Broadband dispersion-engineered microresonator on a chip

Yang, Ki Youl; Beha, Katja; Cole, Daniel C.; Del’Haye, Pascal; Lee, Hansuek; Li, Jiang; Oh, Dong Yoon; Diddams, Scott A.; Vahala, Kerry J.

doi:10.1038/nphoton.2016.36

Cited by 97 publications

(54 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The theoretical efficiency limit is actually 2× higher than shown on this scale, and could be achieved by using a resonator that is highly over coupled. Cavity dispersion control methods have been demonstrated using a modification to the standard wedge resonator process [54]. These same methods might be applied to control dispersive wave generation within the resonator to achieve the direct generation of a broader comb.…”

Section: Discussionmentioning

confidence: 99%

Soliton frequency comb at microwave rates in a high-Q silica microresonator

Yang

Suh

et al. 2015

Optica

Self Cite

524

457

View full text Add to dashboard Cite

Frequency combs are having a broad impact on science and technology because they provide a way to coherently link radio/microwave-rate electrical signals with optical-rate signals derived from lasers and atomic transitions. Integrating these systems on a photonic chip would revolutionize instrumentation, time keeping, spectroscopy, navigation, and potentially create new mass-market applications. A key element of such a system-on-a-chip will be a mode-locked comb that can be self-referenced. The recent demonstration of soliton mode locking in crystalline and silicon nitride microresonators has provided a way to both mode lock and generate femtosecond time-scale pulses. Here, soliton mode locking is demonstrated in high-Q silica resonators. The resonators produce low-phase-noise soliton pulse trains at readily detectable pulse rates-two essential properties for the operation of frequency combs. A method for the long-term stabilization of the solitons is also demonstrated, and is used to test the theoretical dependence of the comb power, efficiency, and soliton existence power on the pulse width. The influence of the Raman process on the soliton existence power and efficiency is also observed. The resonators are microfabricated on silicon chips and feature reproducible modal properties required for soliton formation. A low-noise and detectable pulse rate soliton frequency comb on a chip is a significant step towards a fully integrated frequency comb system.

show abstract

Section: Discussionmentioning

confidence: 99%

Soliton frequency comb at microwave rates in a high-Q silica microresonator

Yang

Suh

et al. 2015

Optica

Self Cite

524

457

View full text Add to dashboard Cite

show abstract

“…With appropriate power and laser-resonator frequency detuning, the resulting fields modelock to form circulating dissipative Kerr-cavity solitons [3][4][5][6][7][8][9][10] . These solitons are pulsed excitations atop a non-zero continuous wave background, and have robust deterministic properties that may be tailored through resonator design 11,12 and tuned in real-time through manipulation of the pump laser. Microcombs based on solitons extend the range of accessible comb repetition rates and provide a route towards chip-integrated self-referenced comb technology.…”

mentioning

confidence: 99%

“…tailored through resonator design 11,12 and tuned in real-time through manipulation of the pump laser. Microcombs based on solitons extend the range of accessible comb repetition rates and provide a route towards chip-integrated self-referenced comb technology.…”

mentioning

confidence: 99%

Soliton crystals in Kerr resonators

et al. 2017

Self Cite

View full text Add to dashboard Cite

Strongly interacting solitons confined to an optical resonator would offer unique capabilities for experiments in communication, computation, and sensing with light. Here we report on the discovery of soliton crystals in monolithic Kerr microresonators-spontaneously and collectively ordered ensembles of co-propagating solitons whose interactions discretize their allowed temporal separations. We unambiguously identify and characterize soliton crystals through analysis of their 'fingerprint' optical spectra, which arise from spectral interference between the solitons. We identify a rich space of soliton crystals exhibiting crystallographic defects, and time-domain measurements directly confirm our inference of their crystal structure. The crystallization we observe is explained by long-range soliton interactions mediated by resonator mode degeneracies, and we probe the qualitative difference between soliton crystals and a soliton liquid that forms in the absence of these interactions. Our work explores the rich physics of monolithic Kerr resonators in a new regime of dense soliton occupation and offers a way to greatly increase the efficiency of Kerr combs; further, the extreme degeneracy of the configuration space of soliton crystals suggests an implementation for a robust on-chip optical buffer.Optical solitons have recently found a new realization in frequency combs generated in passive, monolithic Kerrnonlinear resonators 1 (microcombs). These microcombs are a major step forward in frequency-comb technology 2 because they enable generation of combs in platforms having low size, weight, and power requirements. When a continuous-wave pump laser is coupled into a whispering-gallery mode of a high-Q Kerr resonator, broad optical spectra are generated through cascaded four-wave mixing. With appropriate power and laser-resonator frequency detuning, the resulting fields modelock to form circulating dissipative Kerr-cavity solitons [3][4][5][6][7][8][9][10] . These solitons are pulsed excitations atop a non-zero continuous wave background, and have robust deterministic properties that may be tailored through resonator design 11,12 and tuned in real-time through manipulation of the pump laser. Microcombs based on solitons extend the range of accessible comb repetition rates and provide a route towards chip-integrated self-referenced comb technology.Single solitons and ensembles of several co-propagating solitons have been reported in Kerr resonators constructed from a variety of crystalline and amorphous materials 3-7 , with repetition rates ranging from 22 GHz 6 to 1 THz 7 . Formally equivalent to monolithic Kerr resonators are lower repetition-rate fiber-loop resonators, where generation and control of soliton ensembles has recently been explored experimentally [13][14][15][16] . These experiments were preceded by theoretical studies of soliton interactions and ensembles of solitons in quasi-CW-pumped fiber-ring resonators [17][18][19] , where an analogy between soliton ensembles and the states of matter was introduc...

show abstract

“…The degree to which these interactions can be engineered and controlled is an active area of investigation. Letter Geometrical control of dispersion over broad spectral spans using microfabrication methods [30] could be applicable for dispersivewave control.…”

mentioning

confidence: 99%

Spatial-mode-interaction-induced dispersive waves and their active tuning in microresonators

Yang

Vahala

2016

Optica

Self Cite

View full text Add to dashboard Cite

The nonlinear propagation of optical pulses in dielectric waveguides and resonators induces a wide range of remarkable interactions. One example is dispersive-wave generation, the optical analog of Cherenkov radiation. These waves play an essential role in the fiber-optic spectral broadeners used in spectroscopy and metrology. Dispersive waves form when a soliton pulse begins to radiate power as a result of higher-order dispersion. Recently, dispersive-wave generation in microcavities has been reported by phase matching the waves to dissipative Kerr solitons. Here, it is shown that spatial mode interactions within a microcavity can be used to induce dispersive waves. The soliton self-frequency shift is also shown to enable fine tuning control of the dispersive-wave frequency. Both this mechanism and spatial mode interactions allow spectral control of these important waves in microresonators. If the spectrum of a soliton pulse extends into regions where second-order dispersion changes sign, then radiation into a new pulse, the dispersive wave, may occur at a phase-matching wavelength [1,2]. The generation of these waves is analogous to Cherenkov radiation [3] and extends the spectral reach of optical pulses [4]. The recent ability to control dispersion in microresonators has allowed accurate spectral placement of dispersive waves relative to a radiating cavity soliton [5]. Such dispersionengineered control has made possible 2f-3f self-referencing of frequency microcombs [6] and octave-spanning double-dispersive waves [7]. Dispersive-wave generation in optical fibers has traditionally relied upon control of geometrical dispersion in conjunction with the intrinsic material dispersion of the dielectric [4], and this same method has been successfully demonstrated in microresonators [5]. Recently, spatial mode interactions in multimode fiber have also been used for this purpose [8][9][10].Here, spatial mode interactions within a microresonator are used to phase match a soliton pulse to a dispersive wave. These mode interactions often frustrate the formation of solitons [11] and, as a result, microresonators are typically designed to minimize or exclude entirely the resulting modal avoided crossings [5,[12][13][14][15]. Also, while dispersive wave phase matching is normally induced by more gradual variations in dispersion, spatialmode interactions produce spectrally abrupt variations that can activate a dispersive wave in the vicinity of a narrowband soliton. Below, the demonstration of dispersive-wave generation by this process is presented after characterizing two strongly interacting spatial-mode families. The phase matching of the dispersive wave to the soliton is then studied, including the effect of soliton frequency offset relative to the pump, as is caused by soliton recoil or by the Raman-induced soliton self-frequency shift (SSFS) [5,13,[16][17][18]. It is shown that this mechanism enables active tuning control of the dispersive wave by pump tuning.In the experiment, an ultrahigh-Q silica microresonator (3 mm...

show abstract

Broadband dispersion-engineered microresonator on a chip

Cited by 97 publications

References 62 publications

Soliton frequency comb at microwave rates in a high-Q silica microresonator

Soliton frequency comb at microwave rates in a high-Q silica microresonator

Soliton crystals in Kerr resonators

Spatial-mode-interaction-induced dispersive waves and their active tuning in microresonators

Contact Info

Product

Resources

About