Selfconsistent nonMarkovian theory of a quantumstate evolution for quantuminformation processing
Abstract
We study nonMarkovian decoherence phenomena by employing projectionoperator formalism when a quantum system (a quantum bit or a register of quantum bits) is coupled to a reservoir. By projecting out the degree of freedom of the reservoir, we derive a nonMarkovian master equation for the system, which is reduced to a Lindblad master equation in Markovian limit, and obtain the operator sum representation for the time evolution. It is found that the system is decohered slower in the nonMarkovian reservoir than the Markovian because the quantum information of the system is memorized in the nonMarkovian reservoir. We discuss the potential importance of nonMarkovian reservoirs for quantuminformation processing.
 Publication:

Physical Review A
 Pub Date:
 July 2002
 DOI:
 10.1103/PhysRevA.66.012302
 arXiv:
 arXiv:quantph/0105065
 Bibcode:
 2002PhRvA..66a2302A
 Keywords:

 03.67.a;
 89.70.+c;
 Quantum information;
 Information theory and communication theory;
 Quantum Physics
 EPrint:
 5pages