Spin State Determination Using a Stern-Gerlach Device

Radu Ionicioiu, Irene D’Amico

Carole Duboc, Marcello Gennari

M. Steiner, Michael R. Frey, ARMEN M. GULIAN +2 more

The Stern-Gerlach (SG) apparatus for measuring the spin of an uncharged spin-1/2 particle is the archetypal quantum sensing device. We study this device for the new problem of measuring the spin of a particle that is coupled externally to another particle. Specifically, we treat two coupled particles in which a single particle is measured by the SG device while the other is not. We show simulations of how the binding energy associated with the external coupling is completely converted to potential energy and kinetic energy as the single particle separates spatially within the magnetic field of the SG device. Additionally we show simulations of how the initial particle acceleration within the SG devices relates to the coupling, the quantum state of the two-particle system, and the initial spatial dispersion of the particle within the SG device. The results of our analysis, though obtained specifically for the SG apparatus, may be generic to other quantum measurement devices with similar external coupling.

George H. Rutherford, R. Grobe

M. I. Shirokov

L'objet de cet article est la determination de la fonction d'onde d'un systeme physique soumis a une mesure c'est-a-dire la determination du module et de la phase de cette fonction. Pour determiner l'etat de spin d'une particule, on propose ici une version de l'ezperience de Stern-Gerlach utilisant un champ magnetique inhomogene et faible. On montre que ce modele correspond a une mesure quantique de type non-canonique et on etablit la comparaison avec l'experience classique de Stern-Gerlach. Enfin on discute la possibilite d'une mesure de l'etat de spin sans reduction lorsque l'etat ne change pas pendant la mesure.

Antonio Di Lorenzo