Benabid F, Knight J C, Antonopoulos G, Russell P St J
Optoelectronics Group, Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY, UK.
Science. 2002 Oct 11;298(5592):399-402. doi: 10.1126/science.1076408.
We report on stimulated Raman scattering in an approximately 1-meter-long hollow-core photonic crystal fiber filled with hydrogen gas under pressure. Light was guided and confined in the 15-micrometer-diameter hollow core by a two-dimensional photonic bandgap. Using a pulsed laser source (pulse duration, 6 nanoseconds; wavelength, 532 nanometers), the threshold for Stokes (longer wavelength) generation was observed at pulse energies as low as 800 +/- 200 nanojoules, followed by a coherent anti-Stokes (shorter wavelength) generation threshold at 3.4 +/- 0.7 microjoules. The pump-to-Stokes conversion efficiency was 30 +/- 3% at a pulse energy of only 4.5 microjoules. These energies are almost two orders of magnitude lower than any other reported energy, moving gas-based nonlinear optics to previously inaccessible parameter regimes of high intensity and long interaction length.
我们报道了在一根填充有高压氢气的约1米长的空芯光子晶体光纤中实现的受激拉曼散射。光通过二维光子带隙被引导并限制在直径为15微米的空芯中。使用脉冲激光源（脉冲持续时间为6纳秒，波长为532纳米），在低至800±200纳焦的脉冲能量下观察到了斯托克斯（较长波长）产生的阈值，随后在3.4±0.7微焦处观察到了相干反斯托克斯（较短波长）产生的阈值。在仅4.5微焦的脉冲能量下，泵浦到斯托克斯的转换效率为30±3%。这些能量比其他任何报道的能量低近两个数量级，将基于气体的非线性光学推进到了以前无法达到的高强度和长相互作用长度的参数范围。
