Larmor precession reexamined: Testable correction and its ramifications

TL;DR

This paper reexamines Larmor precession for spin-polarized particles, deriving a modified formula that predicts measurable deviations from the standard relation under certain experimental conditions.

Contribution

It introduces a corrected expression for Larmor precession that accounts for kinetic energy effects, extending the analysis to wave packets and identifying testable deviations.

Findings

Modified Larmor precession formula reduces to standard at high kinetic energies.

Identifies regimes where deviations from standard precession are experimentally detectable.

Provides comparative analysis of standard and modified predictions across parameters.

Abstract

For a spin-polarized plane wave passing through a spin-rotator containing uniform magnetic field, we provide a detailed analysis for solving the appropriate Schr\"{o}dinger equation. A modified expression for spin precession is obtained which reduces to the standard Larmor precession relation when kinetic energy is very large compared to the spin-magnetic field interaction. We show that there are experimentally verifiable regimes of departure from the standard Larmor precession formula. The treatment is then extended to the case of a spin-polarized wave packet passing through a uniform magnetic field. The results based on the standard expression for Larmor precession and that obtained from the modified formula are compared in various regimes of the experimental parameters.