Relativistic electron vortex beams: angular momentum and spin-orbit interaction.
نویسندگان
چکیده
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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عنوان ژورنال:
- Physical review letters
دوره 107 17 شماره
صفحات -
تاریخ انتشار 2011