Relativistic electron spin dynamics in a strong unipolar laser field
arXiv:2005.02839 · doi:10.1103/PhysRevA.102.023102
Abstract
The behavior of an electron spin interacting with a linearly polarized laser field is analyzed. In contrast to previous considerations of the problem, the initial state of the electron represents a localized wave packet, and a spatial envelope is introduced for the laser pulse, which allows one to take into account the finite size of both objects. Special attention is paid to ultrashort pulses possessing a high degree of unipolarity. Within a classical treatment (both nonrelativistic and relativistic), proportionality between the change of the electron spin projections and the electric field area of the pulse is clearly demonstrated. We also perform calculations of the electron spin dynamics according to the Dirac equation. Evolving the electron wave function in time, we compute the mean values of the spin operator in various forms. It is shown that the classical relativistic predictions are accurately reproduced when using the Foldy-Wouthuysen operator. The same results are obtained when using the Lorentz transformation and the nonrelativistic (Pauli) spin operator in the particle's rest frame.
16 pages, 10 figures
References in corpus (9)
- Nonlinear Compton scattering in ultra-short laser pulses
- Non-Linear Compton Scattering of Ultrashort and Ultraintense Laser Pulses
- Ultrarelativistic electron beam polarization in single-shot interaction with an ultraintense laser pulse
- All-optical control of unipolar pulse generation in a resonant medium with nonlinear field coupling
- Spin dynamics in the Kapitza-Dirac effect
- Spin-polarizing interferometric beam splitter for free electrons
- Position and spin in relativistic quantum mechanics
- Position, spin and orbital angular momentum of a relativistic electron
- Spin and localization of relativistic fermions and uncertainty relations