Methods of Cavity-Enhanced Laser Absorption Spectroscopy Using Microresonator Whispering-Gallery Modes

  • A. T. Rosenberger
Part of the Integrated Analytical Systems book series (ANASYS)


Theoretical analysis of, and experimental results using, chemical sensing techniques based on microcavity-enhanced optical absorption are presented. Two methods are described in detail, and several extensions and enhancements of these methods are discussed briefly. Both techniques involve novel applications of tunable diode laser absorption spectroscopy in which cavity enhancement is provided by a dielectric microresonator (<1 mm in diameter) with whispering-gallery modes (WGMs) excited by tapered-fiber coupling. The evanescent component of a WGM allows for interaction with the analyte. The first method is used for the detection of trace gases in the ambient air by measuring the coupling-fiber throughput as the laser scans in frequency. Centimeter effective absorption path lengths are measured, in agreement with theory. The second method employs the observation of thermal bistability to enable measurement of absorption due to a coating applied to, or molecules adsorbed on, the microresonator's surface. Absorption by the water layer on a fused-silica surface agrees with theory, and results for thermal accommodation coefficients and thin-film absorption are also presented.


Free Spectral Range Accommodation Coefficient Tunable Diode Laser Coupling Loss Coupling Fiber 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The following former and current students have made significant contributions to this work: Jeromy Rezac, George Farca, Siyka Shopova, Elijah Dale, and Deepak Ganta. Also contributing were these students and colleagues: Chuck Blackledge, Razvan Stoian, Michael Humphrey, Sarah Bates, Seth Koterba, Jiangquan Zhang, Brian Strecker, Donna Bandy, Bret Flanders, Lee Elizondo, Sitong Yuan, and Mike Lucas. This work was supported by the National Science Foundation under award numbers 0329924 and 0601362, by the Oklahoma Center for the Advancement of Science and Technology under award numbers AR022–052 and AR072–066, by the Oklahoma State Regents for Higher Education, and by ICx Nomadics, Inc.


  1. 1.
    Matsko, A. B.; Ilchenko, V. S., Optical resonators with whispering-gallery modes – Part I: Basics, IEEE J. Sel. Top. Quantum Electron. 2006, 12, 3–14CrossRefGoogle Scholar
  2. 2.
    Ilchenko, V. S.; Matsko, A. B., Optical resonators with whispering-gallery modes – Part II: Applications, IEEE J. Sel. Top. Quantum Electron. 2006, 12, 15–32CrossRefGoogle Scholar
  3. 3.
    Rosenberger, A. T., Analysis of whispering-gallery microcavity-enhanced chemical absorption sensors, Opt. Express 2007, 15, 12959–12964CrossRefGoogle Scholar
  4. 4.
    Farca, G.; Shopova, S. I.; Rosenberger, A. T., Cavity-enhanced laser absorption spectroscopy using microresonator whispering-gallery modes, Opt. Express 2007, 15, 17443–17448CrossRefGoogle Scholar
  5. 5.
    Rosenberger, A. T.; Dale, E. B.; Ganta, D.; Rezac, J. P., Investigating properties of surfaces and thin films using microsphere whispering-gallery modes, In Laser Resonators and Beam Control X; Kudryashov, A. V.; Paxton, A. H.; Ilchenko, V. S., Eds.; Proc. SPIE 2008, 6872, 68720UGoogle Scholar
  6. 6.
    Teraoka, I.; Arnold, S.; Vollmer, F., Perturbation approach to resonance shifts of whispering-gallery modes in a dielectric microsphere as a probe of a surrounding medium, J. Opt. Soc. Am. B 2003, 20, 1937–1946CrossRefGoogle Scholar
  7. 7.
    Hanumegowda, N. M.; Stica, C. J.; Patel, B. C.; White, I.; Fan, X., Refractometric sensors based on microsphere resonators, Appl. Phys. Lett. 2005, 87, 201107CrossRefGoogle Scholar
  8. 8.
    Armani, A. M.; Vahala, K. J., Heavy water detection using ultra-high-Q microcavities, Opt. Lett. 2006, 31, 1896–1898CrossRefGoogle Scholar
  9. 9.
    Savchenkov, A. A.; Matsko, A. B.; Mohageg, M.; Maleki, L., Ringdown spectroscopy of stimulated Raman scattering in a whispering gallery mode resonator, Opt. Lett. 2007, 32, 497–499CrossRefGoogle Scholar
  10. 10.
    Boyd, R. W.; Heebner, J. E., Sensitive disk resonator photonic biosensor, Appl. Opt. 2001, 40, 5742–5747CrossRefGoogle Scholar
  11. 11.
    Humphrey, M. J.; Dale, E.; Rosenberger, A. T.; Bandy, D. K., Calculation of optimal fiber radius and whispering-gallery mode spectra for a fiber-coupled microsphere, Opt. Commun. 2007, 271, 124–131CrossRefGoogle Scholar
  12. 12.
    Gorodetsky, M. L.; Ilchenko, V. S., Optical microsphere resonators: Optimal coupling to high-Q whispering-gallery modes, J. Opt. Soc. Am. B 1999, 16, 147–154CrossRefGoogle Scholar
  13. 13.
    Cai, M.; Painter, O.; Vahala, K. J., Observation of critical coupling in a fiber taper to a silica-microsphere whispering-gallery mode system, Phys. Rev. Lett. 2000, 85, 74–77CrossRefGoogle Scholar
  14. 14.
    Gorodetsky, M. L.; Ilchenko, V. S., High-Q optical whispering-gallery microresonators: Precession approach for spherical mode analysis and emission patterns with prism couplers, Opt. Commun. 1994, 113, 133–143CrossRefGoogle Scholar
  15. 15.
    Westcott, S. L.; Zhang, J.; Shelton, R. K.; Bruce, N. M. K.; Gupta, S.; Keen, S. L.; Tillman, J. W.; Wald, L. B.; Strecker, B. N.; Rosenberger, A. T.; Davidson, R. R.; Chen, W.; Donovan, K. G.; Hryniewicz, J. V., Broadband optical absorbance spectroscopy using a whispering gallery mode microsphere resonator, Rev. Sci. Instrum. 2008, 79, 033106CrossRefGoogle Scholar
  16. 16.
    Rosenberger, A. T.; Rezac, J. P., Whispering-gallery-mode evanescent-wave microsensor for trace-gas detection, In Biomedical Instrumentation Based on Micro- and Nanotechnology; Mariella, R. P., Jr.; Nicolau, D. V., Eds.; Proc. SPIE 2001, 4265, 102–112CrossRefGoogle Scholar
  17. 17.
    Rezac, J. P.; Rosenberger, A. T., Locking a microsphere whispering-gallery mode to a laser, Opt. Express 2001, 8, 605–610CrossRefGoogle Scholar
  18. 18.
    Chou, S.-I; Baer, D. S.; Hanson, R. K., Diode laser absorption measurements of CH3Cl and CH4 near 1.65 μm, Appl. Opt. 1997, 36, 3288–3293CrossRefGoogle Scholar
  19. 19.
    Boschetti, A.; Bassi, D.; Iacob, E.; Iannotta, S.; Ricci, L.; Scotoni, M., Resonant photoacoustic simultaneous detection of methane and ethylene by means of a 1.63-μm diode laser, Appl. Phys. B 2002, 74, 273–278CrossRefGoogle Scholar
  20. 20.
    Rothman, L. S.; Rinsland, C. P.; Goldman, A.; Massie, S. T.; Edwards, D. P.; Flaud, J.-M.; Perrin, A.; Camy-Peyret, C.; Dana, V.; Mandin, J.-Y.; Schroeder, J.; McCann, A.; Gamache, R. R.; Wattson, R. B.; Yoshino, K.; Chance, K. V.; Jucks, K. W.; Brown, L. R.; Nemtchinov, V.; Varanasi, P., The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition, J. Quant. Spectrosc. Radiat. Transfer 1998, 60, 665–710CrossRefGoogle Scholar
  21. 21.
    von Klitzing, W.; Long, R.; Ilchenko, V. S.; Hare, J.; Lefèvre-Seguin, V., Tunable whispering gallery modes for spectroscopy and CQED experiments, New J. Phys. 2001, 3, 14.1–14.14Google Scholar
  22. 22.
    Farca, G., Cavity-Enhanced Evanescent-Wave Chemical Sensing Using Microresonators, PhD dissertation, Oklahoma State University, 2006 Google Scholar
  23. 23.
    Smith, D. D.; Chang, H.; Fuller, K. A.; Rosenberger, A. T.; Boyd, R. W., Coupled-resonator-induced transparency, Phys. Rev. A. 2004, 69, 063804CrossRefGoogle Scholar
  24. 24.
    Naweed, A.; Farca, G.; Shopova, S. I.; Rosenberger, A. T., Induced transparency and absorption in coupled whispering-gallery microresonators, Phys. Rev. A 2005, 71, 043804CrossRefGoogle Scholar
  25. 25.
    Shopova, S. I.; Blackledge, C. W.; Rosenberger, A. T.; Materer, N. F., Gold nanorods grown from HgTe nanoparticles directly on various surfaces, Appl. Phys. Lett. 2006, 89, 023120CrossRefGoogle Scholar
  26. 26.
    Shopova, S. I., Nanoparticle-Coated Optical Microresonators for Whispering-Gallery Lasing and Other Applications, PhD dissertation, Oklahoma State University, 2007 Google Scholar
  27. 27.
    Shopova, S. I.; Blackledge, C. W.; Rosenberger, A. T., Enhanced evanescent coupling to whispering-gallery modes due to gold nanorods grown on the microresonator surface, Appl. Phys. B 2008, 93, 183–187CrossRefGoogle Scholar
  28. 28.
    Il'chenko, V. S.; Gorodetskii, M. L., Thermal nonlinear effects in optical whispering gallery microresonators, Laser Phys. 1992, 2, 1004–1009Google Scholar
  29. 29.
    Collot, L.; Lefèvre-Seguin, V.; Brune, M.; Raimond, J.-M.; Haroche, S., Very high-Q whispering-gallery mode resonances observed on fused silica microspheres, Europhys. Lett. 1993, 23, 327–334CrossRefGoogle Scholar
  30. 30.
    Carmon, T.; Yang, L.; Vahala, K. J., Dynamical thermal behavior and thermal self-stability of microcavities, Opt. Express 2004, 12, 4742–4750CrossRefGoogle Scholar
  31. 31.
    Malitson, I. H., Interspecimen comparison of the refractive index of fused silica, J. Opt. Soc. Am. 1965, 55, 1205–1209CrossRefGoogle Scholar
  32. 32.
    Rezac, J. P., Properties and Applications of Whispering-Gallery Mode Resonances in Fused Silica Microspheres, PhD dissertation, Oklahoma State University, 2002 Google Scholar
  33. 33.
    Carslaw, H. S.; Jaeger, J. C., Conduction of Heat in Solids, Clarendon, Oxford, 1959, Chap. IX, 230–254Google Scholar
  34. 34.
    Foss, W. R.; Davis, E. J., Transient laser heating of single solid microspheres, Chem. Eng. Commun. 1996, 152–153, 113–138CrossRefGoogle Scholar
  35. 35.
    Kennard, E. H., Kinetic Theory of Gases, McGraw-Hill, New York, NY, 1938, Chap. VIII, 291–337Google Scholar
  36. 36.
    Rogach, A. L.; Koktysh, D. S.; Harrison, M.; Kotov, N. A., Layer-by-layer assembled films of HgTe nanocrystals with strong infrared emission, Chem. Mater. 2000, 12, 1526–1528CrossRefGoogle Scholar
  37. 37.
    Saxena, S. C.; Joshi, R. K., Thermal accommodation and adsorption coefficients of gases, In Vol. II-1 of McGraw-Hill/CINDAS Data Series on Material Properties; Touloukian, Y. S.; Ho, C. Y., Eds.; McGraw-Hill, New York, NY, 1981Google Scholar
  38. 38.
    Vernooy, D. W.; Ilchenko, V. S.; Mabuchi, H.; Streed, E. W.; Kimble, H. J., High-Q measurements of fused-silica microspheres in the near infrared, Opt. Lett. 1998, 23, 247–249CrossRefGoogle Scholar
  39. 39.
    Rokhsari, H.; Spillane, S. M.; Vahala, K. J., Loss characterization in microcavities using the thermal bistability effect, Appl. Phys. Lett. 2004, 85, 3029–3031CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • A. T. Rosenberger
    • 1
  1. 1.Department of PhysicsOklahoma State UniversityStillwaterUSA

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