Direct observation of time-dependent coherent chiral tunneling dynamics

Superpositions of handed molecular states give rise to achiral eigenstates, delocalized across a double-well potential via tunneling. In principle, a coherent superposition of these stationary eigenstates could dynamically relocalize the molecules into chiral states, which has only been demonstrated theoretically. Here, we present a microwave six-wave mixing pump-probe study to create and probe coherent chiral tunneling dynamics in a rotational state. Through a time-resolved scheme, we uncover the periodic time evolution of the induced chiral wavepacket under field-free conditions, using enantiomeric excess as the observable. We also demonstrate precise phase control of this coherence via phase modulation during pump excitation. Our results offer foundational evidence for the superposition principle in chiral tunneling systems, with implications for advancing quantum control in these system.