logo

SCIENCE CHINA Information Sciences, Volume 63 , Issue 11 : 212401(2020) https://doi.org/10.1007/s11432-019-2662-x

Kerr frequency comb with varying FSR spacing based on Si$_3$N$_4$ micro-resonator

More info
  • ReceivedMay 10, 2019
  • AcceptedSep 2, 2019
  • PublishedJun 28, 2020

Abstract

In this paper, we experimentally investigate a novel feedback loop scheme to generate optical frequency comb with varying free spectral range (FSR) spacing in a high-Q silicon nitride (Si$_3$N$_4$) micro-ring resonator. By selecting and amplifying different feedback sidebands, comb line spacing varying from 1-fold to 6-fold FSRs is successfully achieved. This approach could be beneficial to tune the comb repetition rate which is an important parameter for many applications, such as optical coherent communications, optical metrology and arbitrary waveform generation.


Acknowledgment

This work was supported by National Natural Science Foundation of China (Grant Nos. 61335002, 11574102, 61675084, 61775094) and National High Technology Research and Development Program of China (Grant No. 2015AA016904).


References

[1] Pasquazi A, Peccianti M, Razzari L. Micro-combs: A novel generation of optical sources. Phys Rep, 2018, 729: 1-81 CrossRef Google Scholar

[2] Kippenberg T J, Holzwarth R, Diddams S A. Microresonator-based optical frequency combs.. Science, 2011, 332: 555-559 CrossRef PubMed Google Scholar

[3] Pfeifle J, Brasch V, Lauermann M. Coherent terabit communications with microresonator Kerr frequency combs.. Nat Photon, 2014, 8: 375-380 CrossRef PubMed Google Scholar

[4] Marin-Palomo P, Kemal J N, Karpov M. Microresonator-based solitons for massively parallel coherent optical communications.. Nature, 2017, 546: 274-279 CrossRef PubMed Google Scholar

[5] Suh M G, Yang Q F, Yang K Y. Microresonator soliton dual-comb spectroscopy.. Science, 2016, 354: 600-603 CrossRef PubMed Google Scholar

[6] Papp S B, Beha K, Del'Haye P. Microresonator frequency comb optical clock. Optica, 2014, 1: 10-14 CrossRef Google Scholar

[7] Ferdous F, Miao H, Leaird D E. Spectral line-by-line pulse shaping of on-chip microresonator frequency combs. Nat Photon, 2011, 5: 770-776 CrossRef Google Scholar

[8] Obrzud E, Rainer M, Harutyunyan A. A microphotonic astrocomb. Nat Photon, 2019, 13: 31-35 CrossRef Google Scholar

[9] Kues M, Reimer C, Roztocki P. On-chip generation of high-dimensional entangled quantum states and their coherent control.. Nature, 2017, 546: 622-626 CrossRef PubMed Google Scholar

[10] Gohle C, Udem T, Herrmann M. A frequency comb in the extreme ultraviolet.. Nature, 2005, 436: 234-237 CrossRef PubMed Google Scholar

[11] Gambetta A, Ramponi R, Marangoni M. Mid-infrared optical combs from a compact amplified Er-doped fiber oscillator.. Opt Lett, 2008, 33: 2671-2673 CrossRef PubMed Google Scholar

[12] Ozharar S, Quinlan F, Ozdur I. Ultraflat Optical Comb Generation by Phase-Only Modulation of Continuous-Wave Light. IEEE Photon Technol Lett, 2008, 20: 36-38 CrossRef Google Scholar

[13] Zhou X, Zheng X, Wen H. All optical arbitrary waveform generation by optical frequency comb based on cascading intensity modulation. Optics Commun, 2011, 284: 3706-3710 CrossRef Google Scholar

[14] Savchenkov A A, Matsko A B, Ilchenko V S. Tunable optical frequency comb with a crystalline whispering gallery mode resonator.. Phys Rev Lett, 2008, 101: 093902 CrossRef PubMed Google Scholar

[15] Pasquazi A, Caspani L, Peccianti M. Self-locked optical parametric oscillation in a CMOS compatible microring resonator: a route to robust optical frequency comb generation on a chip.. Opt Express, 2013, 21: 13333-13341 CrossRef PubMed Google Scholar

[16] Hausmann B J M, Bulu I, Venkataraman V. Diamond nonlinear photonics. Nat Photon, 2014, 8: 369-374 CrossRef Google Scholar

[17] Wang C, Zhu R R, Hu H, et al. Monolithic photonic circuits for Kerr frequency comb generation, filtering and modulation. 2018,. arXiv Google Scholar

[18] Wilson D J, Schneider K, Hoenl S, et al. Gallium phosphide nonlinear photonics. 2018,. arXiv Google Scholar

[19] Song Q H. Emerging opportunities for ultra-high Q whispering gallery mode microcavities. Sci China-Phys Mech Astron, 2019, 62: 74231 CrossRef Google Scholar

[20] Hao Z Z, Zhang L, Gao A. Periodically poled lithium niobate whispering gallery mode microcavities on a chip. Sci China-Phys Mech Astron, 2018, 61: 114211 CrossRef Google Scholar

[21] Ikeda K, Saperstein R E, Alic N. Thermal and Kerr nonlinear properties of plasma-deposited silicon nitride/ silicon dioxide waveguides.. Opt Express, 2008, 16: 12987-12994 CrossRef PubMed Google Scholar

[22] Xue X, Xuan Y, Liu Y. Mode-locked dark pulse Kerr combs in normal-dispersion microresonators. Nat Photon, 2015, 9: 594-600 CrossRef Google Scholar

[23] Miller S A, Okawachi Y, Ramelow S. Tunable frequency combs based on dual microring resonators.. Opt Express, 2015, 23: 21527-21540 CrossRef PubMed Google Scholar

[24] Jung H, Xiong C, Fong K Y. Optical frequency comb generation from aluminum nitride microring resonator.. Opt Lett, 2013, 38: 2810-2813 CrossRef PubMed Google Scholar

[25] Papp S B, Del'Haye P, Diddams S A. Parametric seeding of a microresonator optical frequency comb.. Opt Express, 2013, 21: 17615 CrossRef PubMed Google Scholar

[26] Johnson A R, Okawachi Y, Lamont M R E. Microresonator-based comb generation without an external laser source.. Opt Express, 2014, 22: 1394 CrossRef PubMed Google Scholar

[27] Wang W Q, Chu S T, Little B E. Dual-pump Kerr Micro-cavity Optical Frequency Comb with varying FSR spacing.. Sci Rep, 2016, 6: 28501 CrossRef PubMed Google Scholar

[28] Wang W Q, Zhang W F, Chu S T. Repetition Rate Multiplication Pulsed Laser Source Based on a Microring Resonator. ACS Photonics, 2017, 4: 1677-1683 CrossRef Google Scholar

[29] Okawachi Y, Saha K, Levy J S. Octave-spanning frequency comb generation in a silicon nitride chip.. Opt Lett, 2011, 36: 3398-3400 CrossRef PubMed Google Scholar

[30] Tan D T H, Ikeda K, Sun P C. Group velocity dispersion and self phase modulation in silicon nitride waveguides. Appl Phys Lett, 2010, 96: 061101 CrossRef Google Scholar

[31] Okawachi Y, Lamont M R E, Luke K, et al. Bandwidth shaping of microresonator-based frequency combs via dispersionengineering. Opt Let, 2014, 39: 3535--3538. Google Scholar

[32] Ferdous F, Miao H, Wang P H. Probing coherence in microcavity frequency combs via optical pulse shaping.. Opt Express, 2012, 20: 21033 CrossRef PubMed Google Scholar

  • Figure 1

    (Color online) Dispersion simulations for the fundamental TE mode of a Si$_3$N$_4$ waveguide with a height of 800 nm and widths of 1500 and 2000 nm. Insets are the modal power profiles at 1550 nm wavelength.

  • Figure 2

    (Color online) (a) The experimental setup for combs generation. (b) The transmission spectrum of the Si$_3$N$_4$ micro-resonator with a cross section of 800–2000 nm. (c) The quality factor of the micro-resonator. (d) Optical frequency combs spectra generated in the Si$_3$N$_4$ micro-resonator. The inset shows the top view of the Si$_3$N$_4$ micro-ring resonator with a height of 800 nm and a width of 2000 nm.

  • Figure 3

    (Color online) (a) The transmission spectrum of the Si$_3$N$_4$ micro-resonator with a cross section of 800 nm$\times$1500 nm. (b) The quality factor of the micro-resonator is 8.24$\times$10$^5$. (c)–(f) Evolution of the frequency comb as the wavelength is gradually tuned to the resonant wavelength from a micro-ring with a cross section of 800 nm$\times$ protectłinebreak 1500 nm. When the wavelength approaches the resonance, peaks start to appear with fourteen FSRs spacing, as shown in (c). Secondary lines gradually fill in the spectral gaps when the wavelength becomes closer to the resonance and FSRs spacing decreases to one FSR as observed in (d)–(f).

  • Figure 4

    (Color online) (a) Experimental setup for combs generation with feedback loop. The inset shows the micro-resonator formed by 800 nm$\times$1500 nm Si$_3$N$_4$ waveguides. (b)–(d) Spectra of the combs with flexible FSR spacing. (b) 2-FSRs, (c) 4-FSRs, (d) 6-FSRs.

Copyright 2020  CHINA SCIENCE PUBLISHING & MEDIA LTD.  中国科技出版传媒股份有限公司  版权所有

京ICP备14028887号-23       京公网安备11010102003388号