Noiseless Quantum Codes
Abstract
In this paper we study a model quantum register R made of N 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 N large enough, in the Hilbert space of R there exists a linear subspace CN which is dynamically decoupled from the environment. The states in CN evolve unitarily and are therefore decoherence-dissipation free. The space CN realizes a noiseless quantum code in which information can be stored, in principle, for an arbitrarily long time without being affected by errors.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 1997
- DOI:
- 10.1103/PhysRevLett.79.3306
- arXiv:
- arXiv:quant-ph/9705044
- Bibcode:
- 1997PhRvL..79.3306Z
- Keywords:
-
- Quantum Physics
- E-Print:
- Revised version (to make it accessible to a broader readership) to appear on PRL (4 pages, REVTEX)