Abstract
In this paper we study a model quantum register made of replicas (cells) of a given finite-dimensional quantum system S. Assuming that all cells are coupled with a common environment with equal strength we show that, for large enough, in the Hilbert space of there exists a linear subspace which is dynamically decoupled from the environment. The states in evolve unitarily and are therefore decoherence-dissipation free. The space realizes a noiseless quantum code in which information can be stored, in principle, for an arbitrarily long time without being affected by errors.
- Received 5 December 1996
DOI:https://doi.org/10.1103/PhysRevLett.79.3306
©1997 American Physical Society