Intrinsic sensitivity limits for multiparameter quantum metrology

The quantum Cramer-Rao bound is a cornerstone of modern quantum metrology, as it provides the ultimate precision in parameter estimation. In the multiparameter scenario, this bound becomes a matrix inequality, which can be cast to a scalar form with a properly chosen weight matrix. Multiparameter es...

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Detalles Bibliográficos
Autores: Goldberg, Aaron Z., Sánchez Soto, Luis Lorenzo, Ferretti, Hugo
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/4477
Acceso en línea:https://hdl.handle.net/20.500.14352/4477
Access Level:acceso abierto
Palabra clave:535
Physics
Multidisciplinary
Óptica (Física)
2209.19 Óptica Física
Descripción
Sumario:The quantum Cramer-Rao bound is a cornerstone of modern quantum metrology, as it provides the ultimate precision in parameter estimation. In the multiparameter scenario, this bound becomes a matrix inequality, which can be cast to a scalar form with a properly chosen weight matrix. Multiparameter estimation thus elicits trade-offs in the precision with which each parameter can be estimated. We show that, if the information is encoded in a unitary transformation, we can naturally choose the weight matrix as the metric tensor linked to the geometry of the underlying algebra Su(n), with applications in numerous fields. This ensures an intrinsic bound that is independent of the choice of parametrization.