Limitations in photoionization of helium by an extreme ultraviolet optical vortex

被引：26

作者：

Kaneyasu, T. ^{[1
]}

Hikosaka, Y. ^{[2
]}

Fujimoto, M. ^{[3
,4
]}

Konomi, T. ^{[3
,4
]}

Katoh, M. ^{[3
,4
]}

Iwayama, H. ^{[3
,4
]}

Shigemasa, E. ^{[3
,4
]}

机构：

[1] SAGA Light Source, Tosu, Saga 8410005, Japan

[2] Toyama Univ, Grad Sch Med & Pharmaceut Sci, Toyama 9300194, Japan

[3] Inst Mol Sci, UVSOR Facil, Okazaki, Aichi 4448585, Japan

[4] Sokendai Grad Univ Adv Studies, Okazaki, Aichi 4448585, Japan

来源：

PHYSICAL REVIEW A | 2017年 / 95卷 / 02期

关键词：

ORBITAL ANGULAR-MOMENTUM; LIGHT; IONS;

D O I：

10.1103/PhysRevA.95.023413

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

Photoelectron angular distributions from helium atoms are measured using the circularly polarized extreme ultraviolet (XUV) vortex produced by a helical undulator as the higher harmonics of its radiation. The XUV vortex has a helical wave front and carries orbital angular momentum as well as the spin angular momentum associated with its circular polarization. While the violation of the electric dipole transition rules has been predicted for interactions between vortices and atoms, the photoelectron angular distributions are well reproduced by assuming electric dipole transitions only. This observation can be explained by the localized nature of the helical phase effect of the vortex on the interaction with atoms, and demonstrates that nondipole interactions induced by the XUV vortex are hardly observable in conventional gas-phase experiments.

引用

页数：7

共 31 条

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