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Journal of Physics Conference Series

Quantum state tomography of the microwave field

George P. Miroshnichenko, O M Korneeva

Published Oct 27, 2014• 0 citations
Publisher

Abstract

We propose a new method for reconstructing the density matrix of a single-mode field of photons in the cavity using the discrete photodetection, which allows studying the quantum field in the microwave range. For reconstruction it is necessary to know the phase quadrature moments of all orders. A method of obtaining the first-order moment is discussed here.

DOI
10.1088/1742-6596/541/1/012101

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We propose a new method for reconstructing the density matrix of a single-mode field of photons in the cavity using the discrete photodetection, which allows studying the quantum field in the microwave range. For reconstruction it is necessary to know the phase quadrature moments of all orders. A method of obtaining the first-order moment is discussed here.
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The protocol of measurement the probability density of a rotated quadrature of microwave mode in an arbitrary quantum state is presented and numerically investigated. The protocol is adapted to the measuring procedure used in the CQED experiments. The method is based on measurement of integrated probability of detection of atoms - probes in the top working state from atoms flying via the cavity. Connection of random variables and is found, when is a qudrature phase. Connection of the tomogram and the tomogram is found. The protocol prescribes the rule of choice of problem parameters, such as interaction time, and the number of atoms in series . The method contains a single fitting parameter that is selected in the process of numerical simulation of the quadrature distribution in a coherent state. Quality selection is determined by the Kolmogorov test. The result of the calculation protocol is a convolution with the instrumental function of the method. The parameters of the instrumental function are shown. Numerical simulations performed for typical numerical values of parameters of the experimental setup, shows the effectiveness of the proposed method.