Abstract
I derive a tight bound between the quality of estimating the state of a single copy of a -level system, and the degree the initial state has to be altered in the course of this procedure. This result provides a complete analytical description of the quantum mechanical trade-off between the information gain and the quantum state disturbance expressed in terms of mean fidelities. I also discuss consequences of this bound for quantum teleportation using nonmaximally entangled states.
- Received 1 May 2000
DOI:https://doi.org/10.1103/PhysRevLett.86.1366
©2001 American Physical Society