Abstract
We find that the fluctuations of the condensate in a weakly interacting Bose gas confined in a box of volume follow the law . This anomalous behavior arises from the occurrence of infrared divergencies due to phonon excitations and holds also for strongly correlated Bose superfluids. The analysis is extended to an interacting Bose gas confined in a harmonic trap where the fluctuations are found to exhibit a similar anomaly.
- Received 7 November 1997
DOI:https://doi.org/10.1103/PhysRevLett.80.5040
©1998 American Physical Society