Traverso Andrew J, Hokr Brett, Yi Zhenhuan, Yuan Luqi, Yamaguchi Shoichi, Scully Marlan O, Yakovlev Vladislav V
Texas A&M University, College Station, Texas 77843, USA.
Saitama University, Saitama City 08544, Japan.
Phys Rev Lett. 2018 Feb 9;120(6):063602. doi: 10.1103/PhysRevLett.120.063602.
In this Letter we present a new technique for attaining efficient low-background coherent Raman scattering where the Raman coherence is mediated by a tunable infrared laser in two-photon resonance with a chosen vibrational transition. In addition to the traditional benefits of conventional coherent Raman schemes, this approach offers a number of advantages including potentially higher emission intensity, reduction of nonresonant four-wave mixing background, preferential excitation of the anti-Stokes field, and simplified phase matching conditions. In particular, this is demonstrated in gaseous methane along the ν_{1} (A_{1}) and ν_{3} (T_{2}) vibrational levels using an infrared field tuned between 1400 and 1600 cm^{-1} and a 532-nm pump field. This approach has broad applications, from coherent light generation to spectroscopic remote sensing and chemically specific imaging in microscopy.
