Studying Electron Tunneling in Liquids with Strong-Field Transient Absorption

Strong-field ionization in the tunneling regime has been extensively studied in the gas phase, including in increasingly large molecular systems. Tunnel ionization in liquids offers a way to study electron tunneling dynamics in a non-periodic medium of higher electron delocalization. Here we present results from a strong-field transient absorption experiment in liquid water. Following excitation by sub-10 fs intense near-IR pulses, we spectrally probe the valence electronic states that are accessible, focusing on dynamics within the first 100 fs. With these results, we seek to understand the importance of intermolecular electron delocalization in tunnel ionization.