title: Subcycle dynamics of Coulomb asymmetry in strong elliptical laser fields.
abstract: We measure photoelectron angular distributions of noble gases in intense elliptically polarized laser fields, which indicate strong structure-dependent Coulomb asymmetry. Using a dedicated semiclassical model, we have disentangled the contribution of direct ionization and multiple forward scattering on Coulomb asymmetry in elliptical laser fields. Our theory quantifies the roles of the ionic potential and initial transverse momentum on Coulomb asymmetry, proving that the small lobes of asymmetry are induced by direct ionization and the strong asymmetry is induced by multiple forward scattering in the ionic potential. Both processes are distorted by the Coulomb force acting on the electrons after tunneling. Lowering the ionization potential, the relative contribution of direct ionization on Coulomb asymmetry substantially decreases and Coulomb focusing on multiple rescattering is more important. We do not observe evident initial longitudinal momentum spread at the tunnel exit according to our simulation.
authors.affiliation: Department of Physics and State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.forename: Yunquan
authors.initials: Y
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Qicheng
authors.initials: Q
authors.lastname: Ning
authors.forename: Libin
authors.initials: L
authors.lastname: Fu
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Yongkai
authors.initials: Y
authors.lastname: Deng
authors.forename: Chengyin
authors.initials: C
authors.lastname: Wu
authors.forename: Liang-You
authors.initials: LY
authors.lastname: Peng
authors.forename: Liangyou
authors.initials: L
authors.lastname: Peng
authors.forename: Qihuang
authors.initials: Q
authors.lastname: Gong