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arXiv · 2307.12436

Polarization of spin-1/2 particles with effective spacetime dependent masses

Samapan Bhadury·Arpan Das·Wojciech Florkowski·Gowthama K. K.·Radoslaw Ryblewski
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Abstract

Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation directly connecting the particle spin tensor with the effective mass. It reflects the conservation of the total angular momentum in a system. In general, we find that the gradients of mass act as a source of the spin polarization. Although this effect is absent for simple boost-invariant dynamics, an extension to non-boost-invariant systems displays a non-trivial dependence of the spin density on the mass indicating that the spin polarization effects may be intertwined with the phenomenon of chiral restoration.

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Samapan Bhadury, Arpan Das, Wojciech Florkowski, Gowthama K. K., Radoslaw Ryblewski. 2023-07-23. Polarization of spin-1/2 particles with effective spacetime dependent masses. https://doi.org/10.1016/j.physletb.2024.138464

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