Optimal strategies for sending information through a quantum channel


Autoria(s): Bagán, Emili (Bagán Capella); Baig, M.; Brey Rodríguez, Antoni; Muñoz Tapia, Ramón; Tarrach, R., 1948-
Contribuinte(s)

Universitat de Barcelona

Data(s)

09/06/2010

Resumo

Quantum states can be used to encode the information contained in a direction, i.e., in a unit vector. We present the best encoding procedure when the quantum state is made up of N spins (qubits). We find that the quality of this optimal procedure, which we quantify in terms of the fidelity, depends solely on the dimension of the encoding space. We also investigate the use of spatial rotations on a quantum state, which provide a natural and less demanding encoding. In this case we prove that the fidelity is directly related to the largest zeros of the Legendre and Jacobi polynomials. We also discuss our results in terms of the information gain.

Identificador

http://hdl.handle.net/2445/12806

Idioma(s)

eng

Publicador

American Physical Society

Direitos

(c) American Physical Society, 2000

info:eu-repo/semantics/openAccess

Palavras-Chave #Teoria quàntica #Teoria de camps (Física) #Quantum theory #Field theory (Physics)
Tipo

info:eu-repo/semantics/article