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Title: Generalized Limits for Single-Parameter Quantum Estimation

Abstract

We develop generalized bounds for quantum single-parameter estimation problems for which the coupling to the parameter is described by intrinsic multisystem interactions. For a Hamiltonian with k-system parameter-sensitive terms, the quantum limit scales as 1/N{sup k}, where N is the number of systems. These quantum limits remain valid when the Hamiltonian is augmented by any parameter-independent interaction among the systems and when adaptive measurements via parameter-independent coupling to ancillas are allowed.

Authors:
; ; ;  [1]
  1. Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States)
Publication Date:
OSTI Identifier:
20957690
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevLett.98.090401; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COUPLING; HAMILTONIANS; INTERACTIONS; QUANTUM FIELD THEORY; QUANTUM MECHANICS

Citation Formats

Boixo, Sergio, Flammia, Steven T., Caves, Carlton M., and Geremia, JM. Generalized Limits for Single-Parameter Quantum Estimation. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.090401.
Boixo, Sergio, Flammia, Steven T., Caves, Carlton M., & Geremia, JM. Generalized Limits for Single-Parameter Quantum Estimation. United States. doi:10.1103/PHYSREVLETT.98.090401.
Boixo, Sergio, Flammia, Steven T., Caves, Carlton M., and Geremia, JM. Fri . "Generalized Limits for Single-Parameter Quantum Estimation". United States. doi:10.1103/PHYSREVLETT.98.090401.
@article{osti_20957690,
title = {Generalized Limits for Single-Parameter Quantum Estimation},
author = {Boixo, Sergio and Flammia, Steven T. and Caves, Carlton M. and Geremia, JM},
abstractNote = {We develop generalized bounds for quantum single-parameter estimation problems for which the coupling to the parameter is described by intrinsic multisystem interactions. For a Hamiltonian with k-system parameter-sensitive terms, the quantum limit scales as 1/N{sup k}, where N is the number of systems. These quantum limits remain valid when the Hamiltonian is augmented by any parameter-independent interaction among the systems and when adaptive measurements via parameter-independent coupling to ancillas are allowed.},
doi = {10.1103/PHYSREVLETT.98.090401},
journal = {Physical Review Letters},
number = 9,
volume = 98,
place = {United States},
year = {Fri Mar 02 00:00:00 EST 2007},
month = {Fri Mar 02 00:00:00 EST 2007}
}
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