Light with orbital angular momentum interacting with trapped ions

Abstract

We study the interaction of a light beams carrying angular momentum with a single, trapped and well localized ion. We provide a detailed calculation of selection rules and excitation probabilities for quadrupole transitions. The results show the dependencies on the angular momentum and polarization of the laser beam as well as the direction of the quantization magnetic field. In order to observe optimally the specific effects, focusing the angular momentum beam close to the diffraction limit is required. We discuss a protocol for examining experimentally the effects on the S${}_{1/2}$ to D${}_{5/2}$ transition using a ${}^{40}$Ca${}^{+}$ ion. Various applications and advantages are expected when using light carrying angular momentum: In quantum information processing, where qubit states of ion crystals are controlled, parasitic light shifts could be avoided as the ion is excited in the dark zone of the beam at zero electric field amplitude. Such interactions also open the door to high dimensional entanglement between light and matter. In spectroscopy one might access transitions which have escaped excitation so far due to vanishing transition dipole moments.

9 pages, 5 figures, to appear in EPJD Topical issue on High Dimensional Quantum Entanglement

References in corpus (6)

• Quantized Rotation of Atoms From Photons with Orbital Angular Momentum
• Towards fault-tolerant quantum computing with trapped ions
• Two-dimensional Bose-Einstein condensate in an optical surface trap
• Angular momentum of focused beams: beyond the paraxial approximation
• Rydberg excitation of trapped cold ions: A detailed case study
• Observing the phase space trajectory of an entangled matter wave packet

Cited by in corpus (3)

• Excitation of E1-forbidden Atomic Transitions with Electric, Magnetic or Mixed Multipolarity in Light Fields Carrying Orbital and Spin Angular Momentum
• Thermal equilibrium spin torque: Near-field radiative angular momentum transfer in magneto-optical media
• Pure circularly polarized light emission from waveguide microring resonators