Research

PKU researchers make progress in strong-field tunneling ionization of atoms

AUG . 24 2017
Peking University, Aug. 24, 2017: The research team of Extreme optics leaded by Professor Liu Yunquan and Professor Gong Qihuang at Peking University investigated the phase distribution of electron wave packets from strong-field tunneling ionization of atoms.

They have measured photoelectron momentum distributions of Ar atoms in orthogonally polarized two-color laser fields with comparable intensities. The synthesized laser field was used to manipulate the oscillating tunneling barrier and the subsequent motion of electrons onto two spatial dimensions. The subcycle structures associated with the temporal double-slit interference are spatially separated and enhanced. They used such a spatiotemporal interferometer to reveal sub-barrier phase of strong-field tunneling ionization.

This study shows that the tunneling process transfers the initial phase onto momentum distribution. Their work has the implication that the sub-barrier phase plays an indispensable role in photoelectron interference processes.

Edited by: Zhang Jiang
Source: School of Physics