6533b85bfe1ef96bd12babf0
RESEARCH PRODUCT
Oscillations of the purity in the repeated-measurement-based generation of quantum states
Hiromichi NakazatoAntonino MessinaBenedetto MilitelloKazuya Yuasasubject
PhysicsQuantum PhysicsQuantum opticFOS: Physical sciencesTransition of stateQuantum capacitySettore FIS/03 - Fisica Della MateriaAtomic and Molecular Physics and OpticsQuantum stateQuantum mechanicsQuantum processFoundations of quantum mechanicCoherent control of atomic interactions with photonQuantum systemQuantum operationInitial value problemQuantum Physics (quant-ph)Quantum computerdescription
Repeated observations of a quantum system interacting with another one can drive the latter toward a particular quantum state, irrespectively of its initial condition, because of an {\em effective non-unitary evolution}. If the target state is a pure one, the degree of purity of the system approaches unity, even when the initial condition of the system is a mixed state. In this paper we study the behavior of the purity from the initial value to the final one, that is unity. Depending on the parameters, after a finite number of measurements, the purity exhibits oscillations, that brings about a lower purity than that of the initial state, which is a point to be taken care of in concrete applications.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-01-01 |