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arXiv · 1105.0331

Relativistic Electron Vortex Beams: Angular Momentum and Spin-Orbit Interaction

Konstantin Y. Bliokh·Mark R. Dennis·Franco Nori
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Abstract

Motivated by the recent discovery of electron vortex beams carrying orbital angular momentum (AM), we construct exact Bessel-beam solutions of the Dirac equation. They describe relativistic and nonparaxial corrections to the scalar electron beams. We describe the spin and orbital AM of the electron with Berry-phase corrections and predict the intrinsic spin-orbit coupling in free space. This can be observed as a spin-dependent probability distribution of the focused electron vortex beams. Moreover, the magnetic moment is calculated, which shows different $g$-factors for spin and orbital AM and also contains the Berry-phase correction.

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Konstantin Y. Bliokh, Mark R. Dennis, Franco Nori. 2011-09-11. Relativistic Electron Vortex Beams: Angular Momentum and Spin-Orbit Interaction. https://doi.org/10.1103/physrevlett.107.174802

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