title: Bohr-Sommerfeld quantization of spin Hamiltonians.
abstract: The Bohr-Sommerfeld rule for a spin system is obtained, including the first quantum corrections. The rule applies to both integer and half-integer spin. It is tested for various models, in particular, the Lipkin-Meshkov-Glick model, and found to agree very well with exact results.
authors.affiliation: Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA. agarg@northwestern.edu
authors.forename: Anupam
authors.initials: A
authors.lastname: Garg
authors.forename: Michael
authors.initials: M
authors.lastname: Stone