Makhija, V.; Veyrinas, K.; Boguslavskiy, A.E.; Forbes, R.; Wilkinson, I.; Lausten, R.; Neville, S.P.; Pratt, S.T.; Schuurman, M.S.; Stolow, A.: Ultrafast Molecular Frame Electronic Coherences from Lab Frame Scattering Anisotropies. Journal of Physics B 53 (2020), p. 114001/1-13
10.1088/1361-6455/ab7a84
Open Accesn Version

Abstract:
Electronic coherences in molecules are ultrafast charge oscillations on the Molecular Frame (MF) and their direct observation and separation from electronic population dynamics is challenging. Here we present a valence shell Lab Frame (LF) scattering method suited to probing electronic coherences in isolated systems. MF electronic coherences lead to LF electronic anisotropies observable by ultrafast angle-resolved scattering. Moment analysis of the LF anisotropy completely separates electronic coherences from population dynamics, demonstrated in excited state NH3 using ultrafast time-energy-angle-resolved photoelectron spectroscopy. This general approach applies equally to attosecond/femtosecond electronic coherences in isolated systems.