The physics that governs quantum monitoring may involve other degrees of freedom than the ones initialised and controlled for probing. In this context we address the simultaneous estimation of phase and dephasing characterizing a dispersive medium, and we explore the role of frequency correlations within a photon pair generated via parametric down-conversion, when used as a probe for the medium. We derive the ultimate quantum limits on the estimation of the two parameters, by calculating the corresponding quantum Cramér-Rao bound; we then consider a feasible estimation scheme, based on the measurement of Stokes operators, and address its absolute performances in terms of the correlation parameters, and, more fundamentally, of the role played by correlations in the simultaneous achievability of the quantum Cramér- Rao bounds for each of the two parameters.
Monitoring dispersive samples with single photons: the role of frequency correlations / E. Roccia, M.G. Genoni, L. Mancino, I. Gianani, M. Barbieri, M. Sbroscia. - In: QUANTUM MEASUREMENTS AND QUANTUM METROLOGY. - ISSN 2299-114X. - 4:1(2017), pp. 64-69. [10.1515/qmetro-2017-0008]
Monitoring dispersive samples with single photons: the role of frequency correlations
M.G. Genoni;
2017
Abstract
The physics that governs quantum monitoring may involve other degrees of freedom than the ones initialised and controlled for probing. In this context we address the simultaneous estimation of phase and dephasing characterizing a dispersive medium, and we explore the role of frequency correlations within a photon pair generated via parametric down-conversion, when used as a probe for the medium. We derive the ultimate quantum limits on the estimation of the two parameters, by calculating the corresponding quantum Cramér-Rao bound; we then consider a feasible estimation scheme, based on the measurement of Stokes operators, and address its absolute performances in terms of the correlation parameters, and, more fundamentally, of the role played by correlations in the simultaneous achievability of the quantum Cramér- Rao bounds for each of the two parameters.File | Dimensione | Formato | |
---|---|---|---|
QMQM_FrequencyCorrelations.pdf
accesso aperto
Tipologia:
Pre-print (manoscritto inviato all'editore)
Dimensione
405.95 kB
Formato
Adobe PDF
|
405.95 kB | Adobe PDF | Visualizza/Apri |
[Quantum Measurements and Quantum Metrology] Monitoring dispersive samples with single photons the role of frequency correlations.pdf
accesso aperto
Tipologia:
Publisher's version/PDF
Dimensione
508.49 kB
Formato
Adobe PDF
|
508.49 kB | Adobe PDF | Visualizza/Apri |
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.