Berry phases near degeneracies: Beyond the simplest case

Anupam Garg*

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

14 Scopus citations


The Berry phase is reviewed with emphasis on the Berry curvature and the Chern number. The behavior of these quantities and the analytic properties of adiabatically continued wave functions in the vicinity of degeneracies are discussed. An example of a spin Hamiltonian is given in which the Chern numbers associated with the states involved in a double degeneracy are ±2 rather than ±1, as is usually the case. Degeneracies in the spectrum of magnetic molecular solids are discussed.

Original languageEnglish (US)
Article number013006AJP
Pages (from-to)661-670
Number of pages10
JournalAmerican Journal of Physics
Issue number7
StatePublished - Jul 2010

ASJC Scopus subject areas

  • General Physics and Astronomy


Dive into the research topics of 'Berry phases near degeneracies: Beyond the simplest case'. Together they form a unique fingerprint.

Cite this