English

Oscillatory Tunnel Splittings in Spin Systems: A Discrete Wentzel-Kramers-Brillouin Approach

Condensed Matter 2009-10-31 v1 Mathematical Physics math.MP

Abstract

Certain spin Hamiltonians that give rise to tunnel splittings that are viewed in terms of interfering instanton trajectories, are restudied using a discrete WKB method, that is more elementary, and also yields wavefunctions and preexponential factors for the splittings. A novel turning point inside the classically forbidden region is analysed, and a general formula is obtained for the splittings. The result is appled to the \Fe8 system. A previous result for the oscillation of the ground state splitting with external magnetic field is extended to higher levels.

Keywords

Cite

@article{arxiv.cond-mat/9907152,
  title  = {Oscillatory Tunnel Splittings in Spin Systems: A Discrete Wentzel-Kramers-Brillouin Approach},
  author = {Anupam Garg},
  journal= {arXiv preprint arXiv:cond-mat/9907152},
  year   = {2009}
}

Comments

RevTex, one ps figure