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arXiv · 1801.05987

Sum-frequency ionic Raman scattering

Dominik M. Juraschek·Sebastian F. Maehrlein
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Abstract

In a recent report sum-frequency excitation of a Raman-active phonon was experimentally demonstrated for the first time. This mechanism is the sibling of impulsive stimulated Raman scattering, in which difference-frequency components of a light field excite a Raman-active mode. Here we propose that ionic Raman scattering analogously has a sum-frequency counterpart. We compare the four Raman mechanisms, photonic and ionic difference- and sum-frequency excitation, for three different example materials using a generalized oscillator model for which we calculate the parameters with density functional theory. Sum-frequency ionic Raman scattering completes the toolkit for controlling materials properties by means of selective excitation of lattice vibrations.

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Dominik M. Juraschek, Sebastian F. Maehrlein. 2018-01-29. Sum-frequency ionic Raman scattering. https://doi.org/10.1103/physrevb.97.174302

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