# Position, spin and orbital angular momentum of a relativistic electron

@article{Bliokh2017PositionSA, title={Position, spin and orbital angular momentum of a relativistic electron}, author={Konstantin Y. Bliokh and Mark R. Dennis and Franco Nori}, journal={arXiv: Quantum Physics}, year={2017} }

Motivated by recent interest in relativistic electron vortex states, we revisit the spin and orbital angular momentum properties of Dirac electrons. These are uniquely determined by the choice of the position operator for a relativistic electron. We overview two main approaches discussed in the literature: (i) the projection of operators onto the positive-energy subspace, which removes the zitterbewegung effects and correctly describes spin-orbit interaction effects, and (ii) the use of Newton…

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