@article {ISI:000229746300006, title = {High-resolution stimulated Raman gain spectroscopy of parahydrogen crystals}, journal = {JOURNAL OF LOW TEMPERATURE PHYSICS}, volume = {139}, number = {5-6}, year = {2005}, note = {5th International Conference on Cryocrystals and Quantum Crystals (CC 2004), Wroclaw, POLAND, AUG 29-SEP 04, 2004}, month = {JUN}, pages = {515-522}, abstract = {High-resolution stimulated Raman gain spectroscopy of the Q(1)(0) transition of para-H-2 crystals with varying ortho-H-2 concentrations is reported. A crystal containing 0.06\% of ortho-H-2 showed a single sharp Raman transition with the width of less than 7 MHz. The Raman signal became broader with increasing concentration of ortho-H-2. At the concentration of 2\%, the spectrum splits into a doublet. The components of the doublet have different dependence on the relative polarization of the pump and probe laser radiations. Physical origin of the splitting and the polarization dependence is yet to be understood.}, issn = {0022-2291}, doi = {10.1007/s10909-005-5437-3}, author = {Momose, T and Oka, T} }