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Board Members

Oskar J. Painter
Nai-Chang Yeh

Harry A. Atwater, Jr.
Julia R. Greer
James R. Heath
Nathan S. Lewis
Michael Roukes
Axel Scherer
Keith C. Schwab
Kerry J. Vahala


image Kerry J. Vahala
Ted and Ginger Jenkins Professor of Information Science and Technology and Professor of Applied Physics, Executive Officer Applied Physics and Materials Science department

B.S., Caltech, 1980; M.S., 1981; Ph.D., 1985.

phone: 626.395.2144
location: 234 Watson Laboratories
mail code: 128-95

Research Group |

Lightwave communications, ultrafast physics and application to high-speed information processing.

The recent research in the Vahala Group can be broken into several sub-groups:

  • Ultra-High-Q toroidal microresonator: The development of the Ultra-high-Q silica toroidal microresonator has enabled many other devices such as High Q polymer resonators, four port couplers, and tunable microresonators. Additionally, recent results have shown pressure-driven mechanical oscillations present in the toroid.
  • Non-linear Optics: Because of the very small mode volume and the very high-Q of silica microresonators, the power build-up is extremely large. This allows for studies of non-linearities in silica which would otherwise be extremely difficult.
  • Sensing: Quality factors greater than 100 million in water have been achieved in water. These ultra-high-Q factors have enabled ultra-sensitive detection of heavy water heavy water.
  • Rare-Earth Doping: By doping silica with rare earth elements, such as erbium, microlasers are able to be fabricated. We have collaborated with Prof. Albert Polman at FOM on Er+ ion implantation. Additionally, we have used Er+ doped sol-gel and CdSe/ZnS nanocrystals. We have collaborated with Prof. Harry Atwater at Caltech on CdSe/ZnS nanocrystal synthesis.
  • Cavity Quantum Electrodynamics (cavity QED): Simulations have shown that UHQ microtoroids can provide a new and useful resonator platform for cavity QED experiments. In addition, the ability to couple optical power very efficiently to and from the resonator using a tapered optical fiber will be important. We are collaborating with Prof. Jeff Kimble’s group in the Caltech Physics Department to experimentally demonstrate strong coupling between a microtoroid and a single cesium atom.



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