Multi-Electron Effects in Charge Asymmetric Molecules Induced by Asymmetric Laser Fields

Using a 45 fs pump pulse at 800 nm, a wavepacket is created in a charge asymmetric dissociation channel of Iodine, I$_{2}^{2+}$ $\rightarrow$ I$^{2+}$ + I$^{0+}$ (2,0). As the molecule dissociates, a two-color (1$\omega$2$\omega$) probe pulse is used to study the dynamics as a function of internuclear separation $R$. We find a critical region of $R$ in which there is spatially asymmetric enhanced ionization of the (2,0) channel to a counter-intuitive (1,2) channel. In this region the I$^{0+}$ is ionized such that one electron is released to the continuum and another is transfered to the I$^{2+}$ resulting in I$^{0+}$ $\rightarrow$ I$^{2+}$ and I$^{2+}$ $\rightarrow$ I$^{1+}$. At larger $R$, the ionization is consistent with simple one-electron ionization in a double-well where I$^{0+}$ $\rightarrow$ I$^{1+}$. We find qualitative agreement between simulations and experiment further highlighting the importance of multi-electron effects in the strong-field ionization of molecules.