Coherent couplings between discrete sigma orbitals of carbon monoxide driven by external electric fields

Abstract

By applying external electric fields to an architype diatomic molecule, CO, herein we have successfully observed coherent couplings established between two sigma orbitals of the CO molecule. By monitoring orbital evolution in real time, we have discovered that the two sigma orbitals pertain to coherent quantum oscillations in both the electric dipole and elemental charge. This finding essentially points to an important discovery that the electric fields selectively drive the sigma electrons onto new electronic orders of coherent orbital couplings. Such robust couplings among the sigma electrons can be well manipulated based on the discovery that the coupled oscillatory period is in proportion to the strength of the electric fields. Our investigations essentially have brought Bloch oscillations down to single molecular levels with new physical insights, thus opening up a new avenue to probe the very foundations of quantum mechanics with molecules, which may have insightful implications for attosecond correlation dynamics in molecules, and may have a profound impact on controlling electronic states by strong laser fields.