Abstract
The decay of a metastable state is studied by means of a functional-integral approach. Depending on the shape of the potential barrier, the crossover from thermal activation to thermally assisted quantum tunneling is either a first- or second-order phase transition on temperature. Below the crossover temperature, first-order transitions between different tunneling regimes are possible. The general features of these transitions, and the possibilities to observe them, are discussed.
- Received 18 March 1992
DOI:https://doi.org/10.1103/PhysRevA.46.8011
©1992 American Physical Society