title: Controlling the XUV transparency of helium using two-pathway quantum interference.
abstract: Atoms irradiated with combined femtosecond laser and extreme ultraviolet (XUV) fields ionize through multiphoton processes, even when the energy of the XUV photon is below the ionization potential. However, in the presence of two different XUV photons and an intense laser field, it is possible to induce full electromagnetic transparency. Taking helium as an example, the laser field modifies its electronic structure, while the presence of two different XUV photons and the laser field leads to two distinct ionization pathways that can interfere destructively. This work demonstrates a new approach for coherent control in a regime of highly excited states and strong optical fields.
authors.affiliation: JILA and Department of Physics, University of Colorado and NIST, Boulder, Colorado 80309, USA.
authors.forename: P
authors.initials: P
authors.lastname: Ranitovic
authors.forename: X M
authors.initials: XM
authors.lastname: Tong
authors.forename: C W
authors.initials: CW
authors.lastname: Hogle
authors.forename: X
authors.initials: X
authors.lastname: Zhou
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: N
authors.initials: N
authors.lastname: Toshima
authors.forename: M M
authors.initials: MM
authors.lastname: Murnane
authors.forename: H C
authors.initials: HC
authors.lastname: Kapteyn