title: Refractive index measurements of solid parahydrogen.
abstract: Solid para-H2 is a promising gain medium for stimulated Raman scattering, due to its high number density and narrow Raman linewidth. In preparation for the design of a cw solid hydrogen Raman laser, we have made the first measurements, to our knowledge, of the index of refraction of a solid para-H2 crystal, in the wavelength range of 430-1100 nm. For a crystal stabilized at 4.4 K, this refractive index is measured to be n(p-H2)=1.130±0.001 at 514 nm. A slight, but significant, dependence on the final crystal-growth temperature is observed, with higher n(p-H2) at higher crystal-growth temperatures. Once a crystal is grown, it can be heated up to 10 K with no change in n(p-H2). The refractive index varies only slightly over the observed wavelength range, and no significant birefringence was observed.
authors.affiliation: Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA. mperera@illinois.edu
authors.forename: Manori
authors.initials: M
authors.lastname: Perera
authors.forename: Brian A
authors.initials: BA
authors.lastname: Tom
authors.forename: Yuki
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Michael W
authors.initials: MW
authors.lastname: Porambo
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Moore
authors.forename: William R
authors.initials: WR
authors.lastname: Evans
authors.forename: Takamasa
authors.initials: T
authors.lastname: Momose
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: McCall