Next Article in Journal
Object Tracking Based on (m,k)-firm Model in Multimedia Wireless Sensor Networks
Previous Article in Journal
Developing a Vibration-Sensing Yarn for Monitoring Hand-Transmitted Vibrations
Proceeding Paper

Continuous Measurements for Advanced Quantum Metrology

1
Department of Physics, University of Warwick, Coventry CV4 7AL, UK
2
Quantum Technology Lab, Dipartimento di Fisica `Aldo Pontremoli’, Università degli Studi di Milano, IT-20133 Milan, Italy
3
QTF Centre of Excellence, Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turun Yliopisto, Finland
*
Author to whom correspondence should be addressed.
Presented at the 11th Italian Quantum Information Science Conference (IQIS2018), Catania, Italy, 17–20 September 2018.
Proceedings 2019, 12(1), 47; https://doi.org/10.3390/proceedings2019012047
Published: 4 December 2019
(This article belongs to the Proceedings of 11th Italian Quantum Information Science conference (IQIS2018))
We review some recent results regarding the use of time-continuous measurements for quantum-enhanced metrology. First, we present the underlying quantum estimation framework and elucidate the correct figures of merit to employ. We then report results from two previous works where the system of interest is an ensemble of two-level atoms (qubits) and the quantity to estimate is a magnetic field along a known direction (a frequency). In the first case, we show that, by continuously monitoring the collective spin observable transversal to the encoding Hamiltonian, we get Heisenberg scaling for the achievable precision (i.e., 1 / N for N atoms); this is obtained for an uncorrelated initial state. In the second case, we consider independent noises acting separately on each qubit and we show that the continuous monitoring of all the environmental modes responsible for the noise allows us to restore the Heisenberg scaling of the precision, given an initially entangled GHZ state.
Keywords: quantum metrology; quantum estimation; quantum trajectories; continuous measurements quantum metrology; quantum estimation; quantum trajectories; continuous measurements
MDPI and ACS Style

Albarelli, F.; Rossi, M.A.C.; Tamascelli, D.; Genoni, M.G. Continuous Measurements for Advanced Quantum Metrology. Proceedings 2019, 12, 47. https://doi.org/10.3390/proceedings2019012047

AMA Style

Albarelli F, Rossi MAC, Tamascelli D, Genoni MG. Continuous Measurements for Advanced Quantum Metrology. Proceedings. 2019; 12(1):47. https://doi.org/10.3390/proceedings2019012047

Chicago/Turabian Style

Albarelli, Francesco, Matteo A.C. Rossi, Dario Tamascelli, and Marco G. Genoni. 2019. "Continuous Measurements for Advanced Quantum Metrology" Proceedings 12, no. 1: 47. https://doi.org/10.3390/proceedings2019012047

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop