The SternGerlach experiment and the effects of spin relaxation.
(2012) In Physical Chemistry Chemical Physics 14(5). p.16771684 Abstract
 The classical SternGerlach experiment is analyzed with an emphasis on the spin dynamics. The central question asked is whether there occurs a relaxation of the spin angular momentum during the time the particle passes through the SternGerlach magnet. We examine in particular the transverse relaxation, involving angular momentum exchange between the spin of the particles and the spins of the magnet. A method is presented describing relaxation effects at an individual particle level. This leads to a stochastic equation of motion for the spins. This is coupled to a classical equation of motion for the particle translation. The experimental situation is then modeled through simulations of individual trajectories using two sets of parameter... (More)
 The classical SternGerlach experiment is analyzed with an emphasis on the spin dynamics. The central question asked is whether there occurs a relaxation of the spin angular momentum during the time the particle passes through the SternGerlach magnet. We examine in particular the transverse relaxation, involving angular momentum exchange between the spin of the particles and the spins of the magnet. A method is presented describing relaxation effects at an individual particle level. This leads to a stochastic equation of motion for the spins. This is coupled to a classical equation of motion for the particle translation. The experimental situation is then modeled through simulations of individual trajectories using two sets of parameter choices and three different sets of initial conditions. The two main conclusions are: (A) if the coupling between the magnet and the spin is solely described by the Zeeman interaction with the average magnetic field the simulations show a clear disagreement with the experimental observation of Stern and Gerlach. (B) If one, on the other hand, also allows for a T(2) relaxation time shorter than the passage time one can obtain a practically quantitative agreement with the experimental observations. These conclusions are at variance with the standard textbook explanation of the SternGerlach experiment. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/2273604
 author
 Wennerström, Håkan ^{LU} and Westlund, PerOlof
 organization
 publishing date
 2012
 type
 Contribution to journal
 publication status
 published
 subject
 in
 Physical Chemistry Chemical Physics
 volume
 14
 issue
 5
 pages
 1677  1684
 publisher
 Royal Society of Chemistry
 external identifiers

 wos:000299113000018
 pmid:22193591
 scopus:84856015512
 ISSN
 14639084
 DOI
 10.1039/c2cp22173j
 language
 English
 LU publication?
 yes
 id
 0a8bb6a259ce424183eb0ffa56d8e045 (old id 2273604)
 date added to LUP
 20120112 17:07:02
 date last changed
 20180107 07:54:34
@article{0a8bb6a259ce424183eb0ffa56d8e045, abstract = {The classical SternGerlach experiment is analyzed with an emphasis on the spin dynamics. The central question asked is whether there occurs a relaxation of the spin angular momentum during the time the particle passes through the SternGerlach magnet. We examine in particular the transverse relaxation, involving angular momentum exchange between the spin of the particles and the spins of the magnet. A method is presented describing relaxation effects at an individual particle level. This leads to a stochastic equation of motion for the spins. This is coupled to a classical equation of motion for the particle translation. The experimental situation is then modeled through simulations of individual trajectories using two sets of parameter choices and three different sets of initial conditions. The two main conclusions are: (A) if the coupling between the magnet and the spin is solely described by the Zeeman interaction with the average magnetic field the simulations show a clear disagreement with the experimental observation of Stern and Gerlach. (B) If one, on the other hand, also allows for a T(2) relaxation time shorter than the passage time one can obtain a practically quantitative agreement with the experimental observations. These conclusions are at variance with the standard textbook explanation of the SternGerlach experiment.}, author = {Wennerström, Håkan and Westlund, PerOlof}, issn = {14639084}, language = {eng}, number = {5}, pages = {16771684}, publisher = {Royal Society of Chemistry}, series = {Physical Chemistry Chemical Physics}, title = {The SternGerlach experiment and the effects of spin relaxation.}, url = {http://dx.doi.org/10.1039/c2cp22173j}, volume = {14}, year = {2012}, }