Abstract
We have found an exact expression for the decoherence rate of a Josephson charge qubit coupled to fluctuating background charges. At low temperatures the decoherence rate is linear in while at high temperatures it saturates in agreement with a known classical solution which, however, reached at surprisingly high . In contrast to the classical picture, impurity states spread in a wide interval of energies may essentially contribute to .
- Received 22 June 2005
DOI:https://doi.org/10.1103/PhysRevB.72.060509
©2005 American Physical Society