Off-axis excitation of hydrogenlike atoms by twisted photons

Abstract

We show that the twisted photon states, or photon states with large ($>\hslash$) angular momentum projection ($m_{\gamma }$) in the direction of motion, can photoexcite atomic levels for a hydrogen-like atom that are novel and distinct and are not restricted by $m_{\gamma }$, when the symmetry axis of the twisted-photon beam does not coincide with the center of the atomic target. Selection rules are given and interesting implications and observables for the above process are pointed out.

Comments: 8 pages, 5 figures; Version to appear in Physical Review A. arXiv admin note: substantial text overlap with arXiv:1304.0115