The process of high harmonic generation by a long-wavelength driving field has been recently used as an all-optical probe of the band structure of crystals and liquids (e.g. water) [1,2]. These experiments have shown that the tunneled-out electronic wave packet is a sensitive probe of the symmetry structure of the material. Therefore, it can be used as an ultrafast (down to a few-femtosecond) all-optical non-invasive probe of the local order in the generating medium. We intend to extend this investigation to liquid crystal samples.

[1] Vampa, G. et al. Nature 522, 462-464 (2015);

[2] Luu, T.T. et al. Nature Communications, 9 (2018);