title: High-Q UV whispering gallery mode resonators made of angle-cut BBO crystals.
abstract: We report an investigation on angle-cut beta barium borate (BBO) whispering gallery mode (WGM) resonators operating in the ultra violet (UV) wavelength range. A quality (Q) factor of 1.5 × 10(8) has been demonstrated at 370 nm. New upper bounds for the absorption coefficients of BBO are obtained from the Q factor measurements. Moreover, polarization rotations of WGMs in the angle-cut birefringent resonators are observed and investigated. To the best of our knowledge, this is not only the first reported demonstration of an angle-cut WGM resonator but also the first reported high Q WGM resonator in the UV region.
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
authors.forename: Guoping
authors.initials: G
authors.lastname: Lin
authors.forename: Josef
authors.initials: J
authors.lastname: Fürst
authors.forename: Dmitry V
authors.initials: DV
authors.lastname: Strekalov
authors.forename: Ivan S
authors.initials: IS
authors.lastname: Grudinin
authors.forename: Nan
authors.initials: N
authors.lastname: Yu