JoVE Logo
Faculty Resource Center

Sign In





Representative Results






Microwave Photonics Systems Based on Whispering-gallery-mode Resonators

Published: August 5th, 2013



1Optics Department, FEMTO-ST Institute

The customized techniques developed in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators are presented. The protocols to obtain and characterize these resonators are detailed, and an explanation of some of their applications in microwave photonics is given.

Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency.

Whispering gallery mode resonators are disks or spheres of micro- or millimetric radius1,2,3,4. Provided that the resonator is almost perfectly shaped (nanometer-size surface roughness), laser light can be trapped by total internal reflection within its eigenmodes, which are usually referred to as whispering-gallery modes (WGMs). Their free-spectral range (or intermodal frequency) can vary from GHz to THz depending on the resonator's radius, while their quality factor Q can be exceptionally high5, ranging from 107 - 1011. Due to their unique property of stockpiling and slowing down light, WGM optical resonators have....

Log in or to access full content. Learn more about your institution’s access to JoVE content here

The protocol consists in 5 main stages: In the first one, the whispering-gallery-mode resonator is made. In order to control the progress of the polishing of the resonator, surface state measurements are carried out. In the third stage, we fabricate the tool that will launch light in the resonator. Once those two main tools are manufactured, we use them to visualize optical high-Q resonances. Finally, using a high-power input laser beam, the resonator behaves in a nonlinear fashion and Kerr combs are produced.

Log in or to access full content. Learn more about your institution’s access to JoVE content here

This five-step protocol enables to obtain WGM resonators with very high quality factors for microwave photonic applications.

The first step aims to give to the resonator the desired shape, as represented on Scheme 2. The main difficulty here is to manufacture a disk whose rim is sharp enough so that can it strongly confine the trapped photons, without leading to structural fragility from a mechanical standpoint. This polishing tower also possesses remarkable versatility as it .......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

This protocol allows producing high-Q optical resonators, to couple light into them and trigger nonlinear phenomena for various microwave photonics applications.

The first step of rough grinding should give its shape to resonator. After an hour of grinding with the 10 μm abrasive powder, one side of the rim of the resonator should be conveniently shaped (see Scheme 2). The following step will smooth the surface of the resonator and when reaching the stage of the 1 .......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

Y.C.K. acknowledges financial support from the European Research Council through the project NextPhase (ERC StG 278616). Authors also acknowledge support from the Centre National d'Etudes Spatiales (CNES, France) through the Project SHYRO (Action R&T R-S10/LN-0001-004/DA: 10076201), from the ANR project ORA (BLAN 031202), and from the Region de Franche-Comte, France.


Log in or to access full content. Learn more about your institution’s access to JoVE content here

Name Company Catalog Number Comments
Material Name Company
Step motors 50 mm course Thorlabs
3 axis nanostage Physik Instrumente
TUNICS tunable laser source Yenista
Optical spectrum analyzer APEX APEX Technologies

  1. Oraevsky, A. N. Whispering-gallery waves. Quantum Electronics. 32, 377-400 (2002).
  2. Matsko, A. B., Ilchenko, V. S. Optical Resonators With Whispering-Gallery Modes-Part I: Basics. IEEE J. Sel. Top. Quantum Electron. 12, 3-14 (2006).
  3. Ilchenko, V. S., Matsko, A. B. Optical Resonators With Whispering-Gallery Modes-Part II: Applications. IEEE J. Sel. Top. Quantum Electron. 12, 15-32 (2006).
  4. Maker, A. J., Armani, A. M. Fabrication of Silica Ultra High Quality Factor Microresonators. J. Vis. Exp. (65), e4164 (2012).
  5. Savchenkov, A. A., Matsko, A. B., Ilchenko, V. S., Maleki, L. Optical resonators with ten million finesse. Optics Express. 15, 6768-6773 (2007).
  6. Sprenger, B., Schwefel, H. G. L., Lu, Z. H., Svitlov, S., Wang, L. J. CaF2 whispering-gallery-mode-resonator stabilized-narrow-linewidth laser. Optics Letters. 35, 2870-2872 (2010).
  7. Vahala, K. . Optical Microcavities. , (2004).
  8. Matsko, A. B., Savchenkov, A. A., Yu, N., Maleki, L. Whispering-gallery-mode resonators as frequency references. I. Fundamental limitations. J. Opt. Soc. Am. B. 24, 1324-1335 (2007).
  9. Savchenkov, A. A., Matsko, A. B., Ilchenko, V. S., Yu, N. Whispering-gallery mode resonators as frequency references. II. Stabilization. J. Opt. Soc. Am. B. 24, 2988-2997 (2007).
  10. Chembo, Y. K., Baumgartel, L. M., Yu, N. Toward whispering-gallery mode disk resonators for metrological applications. SPIE Newsroom. , (2012).
  11. Armani, D. K., Kippenberg, T. J., Spillane, S. M., Vahala, K. J. Ultra-high-Q toroid microcavity on a chip. Nature. 421, 925-929 (2003).
  12. Hofer, J., Schliesser, A., Kippenberg, T. J. Cavity optomechanics with ultrahigh-Q crystalline microresonators. Phys. Rev. A. 82, 031804 (2010).
  13. Fürst, J. U., Strekalov, D. V., Elser, D., Aiello, A., Andersen, U. L., Marquardt, C. h., Leuchs, G. Quantum Light from a Whispering-Gallery-Mode Disk Resonator. Phys. Rev. Lett. 106, 113901-1-113901-4 (2011).
  14. Del'Haye, P., Schliesser, A., Arcizet, O., Wilken, T., Holzwarth, R., Kippenberg, T. J. Optical frequency comb generation from a monolithic microresonator. Nature. 450, 1214-1217 (2007).
  15. Kippenberg, T. J., Holzwarth, R., Diddams, S. A. Microresonator-Based Optical Frequency Combs. Science. 322, 555-559 (2011).
  16. Spillane, S. M., Kippenberg, T. J., Vahala, K. Ultralow-threshold Raman laser using a spherical dielectric microcavity. Nature. 415, 621-623 (2002).
  17. Liang, W., Ilchenko, V. S., Savchenkov, A. A., Matsko, A. B., Seidel, D., Maleki, L. Passively Mode-Locked Raman Laser. Phys. Rev. Lett. 154, 143903-1-143903-4 (2010).
  18. Grudinin, I. S., Matsko, A., Maleki, L. Brillouin lasing with a CaF2 whispering gallery mode resonator. Phys. Rev. Lett. 102, 043902-1-043902-4 (2009).
  19. Werner, C. S., Beckmann, T., Buse, K., Breunig, I. Blue-pumped whispering gallery optical parametric oscillator. Optics Letters. 37, 4224-4226 (2012).
  20. Knight, J. C., Cheung, G., Jacques, F., Birks, T. A. Phase-matched excitation of whispering gallery-mode resonances by a fiber taper. Opt. Lett. 22, 1129-1131 (1997).
  21. Chembo, Y. K., Yu, N. Modal expansion approach to optical-frequency-comb generation with monolithic whispering-gallery-mode resonators. Phys. Rev. A. 82, 033801-1-033801-18 (2010).
  22. Chembo, Y. K., Strekalov, D. V., Yu, N. Spectrum and Dynamics of Optical Frequency Combs Generated with Monolithic Whispering Gallery Mode Resonators. Phys. Rev. Lett. 104, 103902-1-103902-4 (2010).
  23. Chembo, Y. K., Yu, N. On the generation of octave-spanning optical frequency combs using monolithic whispering-gallery-mode microresonators. Opt. Lett. 35, 2696-2698 (2010).
  24. Brown, N. J. Optical fabrication. Report MISC 4476 1LLNL. , (1990).
  25. Strekalov, D. V., Savchenkov, A. A., Matsko, A. B., Yu, N. Efficient upconversion of subterahertz radiation in a high-Q whispering gallery resonator. Optics Letters. 34, 713-715 (2009).
  26. Dumeige, Y., Trebaol, S., Ghisa, L., Ngan Nguyen, T. K., Tavernier, H., Feron, P. Determination of coupling regime of high-Q resonators and optical gain of highly selective amplifiers. J. Opt. Soc. Am. B. 12, 2073-2080 (2008).
  27. Gorodetsky, M. L., Ilchenko, V. S. Optical microsphere resonators: optimal coupling to high-Q whispering-gallery modes. J. Opt. Soc. Am. B. 16, 147-154 (1999).
  28. Ilchenko, V. S., Yao, X. S., Maleki, L. Pigtailing the high-Q microsphere cavity: a simple fiber coupler for optical whispering-gallery modes. Opt. Let. 24, 723-725 (1999).
  29. Del'Haye, P., Arcizet, O., Schliesser, A., Holzwarth, R. Kippenberg T.J. Full stabilization of a microresonator frequency comb. Phys. Rev. Let. 101, 053903 (2008).

This article has been published

Video Coming Soon

JoVE Logo


Terms of Use





Copyright © 2024 MyJoVE Corporation. All rights reserved