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arXiv · 0706.2408

A New Type of Two-photon Forward Radiation in Pure Liquids

Hong-tao Bian·Yi Rao·Yan-yan Xu·An-an Liu·Yuan Guo·Hong-fei Wang
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Abstract

Unexpected spectral features are observed in the two photon spectrum of the pure water in the forward direction when an 80 femtosecond laser pulse is focused at 10^10Wcm-2 or less. Such intensity is much lower than the breakdown or stimulated threshold of the liquid water. The two broad features are about 2700cm-1 and 5000cm-1 red shifted from the hyper-Rayleigh wavelength, respectively, and they are quadratic with the laser intensity. They do not match the known Raman or hyper-Raman frequencies of water, and they are both centered at a narrow angle in the forward direction. Several other liquids also exhibited similar but molecular specific spectral features.

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Hong-tao Bian, Yi Rao, Yan-yan Xu, An-an Liu, Yuan Guo, Hong-fei Wang. 2007-06-16. A New Type of Two-photon Forward Radiation in Pure Liquids. https://arxiv.org/abs/0706.2408

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