Molecular Orientation-Induced Second Harmonic Generation: deciphering different contributions apart
preprintposted on 2023-01-10, 02:28 authored by Amit Beer, Ran Damari, Yun Chen, Sharly Fleischer
We demonstrate and explore an all-optical technique for direct monitoring the orientation dynamics of gas phase molecular ensembles. The technique termed 'MOISH' utilizes the transiently lifted inversion symmetry of polar gas media and provides a sensitive and spatially localized probing of second harmonic generation signal that is directly correlated with the orientation of the gas. Our experimental results reveal selective electronic and nuclear dynamical contributions to the overall nonlinear optical signal and decipher them apart using the "reporter gas" approach. 'MOISH' provides new, crucial means for exploring controlled rotational dynamics via concerted terahertz and optical field excitation.