Electronic transitions in disc-shaped quantum dots induced by twisted light

TL;DR

This paper theoretically explores how twisted light interacts with disc-shaped quantum dots, revealing selection rules and potential for precise quantum state control, with implications for quantum technologies.

Contribution

It provides a detailed theoretical analysis of light-matter interaction involving twisted light and quantum dots, including transition probabilities and selection rules.

Findings

Transition strength is about 10% of plane-wave excitation.

Selection rule for z-projection of orbital angular momentum is explicitly derived.

Potential for selective electronic state population using tailored light beams.

Abstract

We theoretically investigate the absorption and emission of light carrying orbital angular momentum (twisted-light) by quasi-two-dimensional (disc-shaped) quantum dots in the presence of a static magnetic field. We calculate the transition matrix element for the light-matter interaction and use it to explore different scenarios, depending on the initial and final state of the electron undergoing the optically-induced transition. We make explicit the selection rule for the conservation of the z-projection of the orbital angular momentum. For a realistic set of parameters (quantum dots size, beam waist, photon energy, etc.) the strength of the transition induced by twisted light is 10% of that induced by plane-waves. Finally, our analysis indicates that it may be possible to select precisely the electronic level one wishes to populate using the appropriate combination of light-beam parameters suggesting technological applications to the quantum control of electronic states in quantum dots.