Schwefel, Harald
Date: Thursday, October 23, 2014
Time: 11:00
Place: ETH Zurich, Hönggerberg, HPF G 6
Host: Andreas Wallraff
One ring to bind them all: three wave mixing in non-linear WGM resonators
Harald G. L. Schwefel
Max Planck Institute for the Science of Light, Erlangen, Germany
Efficient coherent conversion of THz or microwave radiation into the near infrared is a challenging but worthwhile endeavor. Nonlinear parametric sum-requency generation conserves both the phase and amplitude of the initial state and is thus ideal for such an attempt. Even in the best second order non-linear crystals however, the non-linearity is so weak, that very high interacting field strengths are necessary for sufficient conversion rates. I will report on generating such high fields within crystalline whispering gallery mode (WGM) resonators. Within such resonators the radiation is bound by total internal reflection along the equator of a convex dielectric, a process that works as well for THz radiation [1,2] as it does for optical light [3,4]. Combined with appropriate phase-matching of the three interacting waves, conversion with a few percent quantum efficiency is possible [1].
1. D. V. Strekalov, H. G. L. Schwefel, A. A. Savchenkov, A. B. Matsko, L. J. Wang, and N. Yu, "Microwave whispering-gallery resonator for efficient optical up-conversion," Phys. Rev. A 80, 033810–5 (2009).
2. S. Preu, H. G. L. Schwefel, S. Malzer, G. H. Döhler, L. J. Wang, M. Hanson, J. D. Zimmerman, and A. C. Gossard, "Coupled whispering gallery mode resonators in the Terahertz frequency range," Opt Express 16, 7336–7343 (2008).
3. F. Sedlmeir, M. Hauer, J. U. Fürst, G. Leuchs, and H. G. L. Schwefel, "Experimental characterization of an uniaxial angle cut whispering gallery mode resonator," Opt. Express 21, 23942–23949 (2013).
4. M. C. Collodo, F. Sedlmeir, B. Sprenger, S. Svitlov, L. J. Wang, and H. G. L. Schwefel, "Sub-kHz lasing of a CaF2 whispering gallery mode resonator stabilized fiber ring laser," Opt. Express 22, 19277–19283 (2014).