Selective and efficient quantum process tomography

In this paper we describe in detail and generalize a method for quantum process tomography that was presented by Bendersky [Phys. Rev. Lett. 100, 190403 (2008)]. The method enables the efficient estimation of any element of the χ matrix of a quantum process. Such elements are estimated as averages o...

Descripción completa

Detalles Bibliográficos
Autores: Bendersky, Ariel Martin, Pastawski, Fernando, Paz, Juan Pablo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/61089
Acceso en línea:http://hdl.handle.net/11336/61089
Access Level:acceso abierto
Palabra clave:Quantum Process Tomography
Quantum Information Processing
Quantum Algorithms
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
https://purl.org/becyt/ford/1.2
Descripción
Sumario:In this paper we describe in detail and generalize a method for quantum process tomography that was presented by Bendersky [Phys. Rev. Lett. 100, 190403 (2008)]. The method enables the efficient estimation of any element of the χ matrix of a quantum process. Such elements are estimated as averages over experimental outcomes with a precision that is fixed by the number of repetitions of the experiment. Resources required implementing it scale polynomially with the number of qubits of the system. The estimation of all diagonal elements of the χ matrix can be efficiently done without any ancillary qubits. In turn, the estimation of all the off-diagonal elements requires an extra clean qubit. The key ideas of the method, which is based on efficient estimation by random sampling over a set of states forming a 2-design, are described in detail. Efficient methods for preparing and detecting such states are explicitly shown. © 2009 The American Physical Society.