Attosecond-resolved photoionization dynamics and interference-enhanced photoelectron circular dichroism in chiral molecules

Chiral molecules exhibit enantiosensitive light–matter interactions, with photoelectron circular dichroism (PECD) serving as a sensitive probe of molecular chirality through the asymmetry in the photoelectron wave-packet amplitude. Here, we theoretically demonstrate a photoelectron interferometric approach to access the phase of the photoelectron wave packet and uncover attosecond dynamics in chiral molecule photoionization. Using circularly polarized attosecond extreme ultraviolet (XUV) pulse trains synchronized with infrared (IR) fields, we reveal distinct time delays between forward- and backward-ejected photoelectrons in a randomly oriented ensemble of chiral molecules. Moreover, we predict a pronounced enhancement of PECD due to the interference of the two photoionization pathways. The forward–backward time delay difference and the PECD are more prominent when the IR field counter-rotates with the XUV field. These results imply the counter-rotating IR field is more efficient in generating odd-parity photoelectron wave packets in continuum–continuum transitions, highlighting the critical role of long-range chiral potential. We demonstrate a way of coherent control over the chiral photoelectron wave packets, providing a route to enhance chiral signals and manipulate ultrafast chiral dynamics on attosecond time scales.