Uncertainty characteristics of generalized quantum measurements

Autor: Holger Friedrich Hofmann
Rok vydání: 2003
Předmět:
Zdroj: Physical Review A. 67
ISSN: 1094-1622
1050-2947
DOI: 10.1103/physreva.67.022106
Popis: The effects of any quantum measurement can be described by a collection of measurement operators {M_m} acting on the quantum state of the measured system. However, the Hilbert space formalism tends to obscure the relationship between the measurement results and the physical properties of the measured system. In this paper, a characterization of measurement operators in terms of measurement resolution and disturbance is developed. It is then possible to formulate uncertainty relations for the measurement process that are valid for arbitrary input states. The motivation of these concepts is explained from a quantum communication viewpoint. It is shown that the intuitive interpretation of uncertainty as a relation between measurement resolution and disturbance provides a valid description of measurement back action. Possible applications to quantum cryptography, quantum cloning, and teleportation are discussed.
8 pages, small additions on cloning and on definitions of delta A_mf, etc
Databáze: OpenAIRE