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Spin dependent observable effect for free particles using the arrival time distribution

Md. Manirul Ali·A. S. Majumdar·D. Home·S. Sengupta
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Abstract

The mean arrival time of free particles is computed using the quantum probability current. This is uniquely determined in the non-relativistic limit of Dirac equation, although the Schroedinger probability current has an inherent non-uniqueness. Since the Dirac probability current involves a spin-dependent term, an arrival time distribution based on the probability current shows an observable spin-dependent effect, even for free particles. This arises essentially from relativistic quantum dynamics, but persists even in the non-relativistic regime.

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Md. Manirul Ali, A. S. Majumdar, D. Home, S. Sengupta. 2003-09-15. Spin dependent observable effect for free particles using the arrival time distribution. https://doi.org/10.1103/physreva.68.042105

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