Abstract
Consider a d-dimensional antiferromagnet with a quantum disordered ground state and a gap to bosonic excitations with nonzero spin. In a finite external magnetic field, this antiferromagnet will undergo a phase transition to a ground state with nonzero magnetization, describable as the condensation of a dilute gas of bosons. The finite-temperature properties of the Bose gas in the vicinity of this transition are argued to obey a hypothesis of zero scale-factor universality for d<2, with logarithmic violations in d=2. Scaling properties of various experimental observables are computed in an expansion in ε=2-d, and exactly in d=1.
- Received 6 January 1994
DOI:https://doi.org/10.1103/PhysRevB.50.258
©1994 American Physical Society
