Abstract

Continuous (nonprojective) measurement on a quantum system has been employed previously for fast, robust, and high-fidelity quantum state tomography (QST) on qudits. We expand this protocol to many-body systems in order to perform QST on the reduced one-body and two-body density matrices of a symmetric many-body state of multiple qubits. Such QST will characterize the spin correlations in the system. In this protocol, a continuous measurement is done collectively on many copies of the reduced state at the same time, and therefore, while it is weakly perturbative on each copy, yields high signal-to-noise. Simultaneously, we subject the system to an external collective control in order to generate an informationally complete measurement record. We characterize the information-gain measurement disturbance tradeoff in terms of parameters in the problem (number of qubits, control parameters, shot-noise …

Date

January 1, 1970

Authors

Ezad Shojaee, Amir Kalev, Ivan Deutsch, Cquic Team

Journal

APS Division of Atomic, Molecular and Optical Physics Meeting Abstracts

Volume

2016

Pages

G4. 008