Open AccessMechanical tuning of whispering gallery modes over a 05 THz tuning range with MHz resolution in a silica microsphere at cryogenic temperatures
Author(s) -
Khodadad Nima Dinyari,
R. James Barbour,
D. Andrew Golter,
Hailin Wang
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.017966
Subject(s) - whispering gallery wave , materials science , optics , microsphere , millimeter , diamond , terahertz radiation , optoelectronics , resonator , composite material , physics , chemical engineering , engineering
We experimentally demonstrate the mechanical tuning of whispering gallery modes in a 40 μm diameter silica microsphere at 10K, over a tuning range of 450 GHz and with a resolution less than 10 MHz. This is achieved by mechanically stretching the stems of a double-stemmed silica microsphere with a commercially available piezo-driven nano-positioner. The large tuning range is made possible by the millimeter long slip-stick motion of the nano-positioner. The ultrafine tuning resolution, corresponding to sub-picometer changes in the sphere diameter, is enabled by the use of relatively long and thin fiber stems, which reduces the effective Poisson ratio of the combined sphere-stem system to approximately 0.0005. The mechanical tuning demonstrated here removes a major obstacle for the use of ultrahigh Q-factor silica microspheres in cavity QED studies of solid state systems and, in particular, cavity QED studies of nitrogen vacancy centers in diamond.