量子レーダー研究のためのスクイーズド光源及びホモダイン測定系の開発

元太政田, Dan Murakami, 丈尚岩越, 正宜相馬

Published Mar 1, 2017• 0 citations

Abstract

We started to research quantum radar based on a quantum illumination method by utilizing continuous-wave two-mode squeezed light as a quantum entanglement resource. Two-mode squeezed light is a macroscopic quantum entangled state of electro-magnetic fields and shows a property of non-classical correlation between quadrature phase amplitudes of each optical field. One of the most effective methods to generate two-mode squeezed light is combining two independent single-mode squeezed light beams by using a beam splitter. As a first step of our work we introduce current development of a single-mode squeezed light source and construction of a balanced homodyne detection part. We utilized a sub-threshold optical parametric oscillator to generate squeezed light and observed the noise level of squeezed quadrature at －3.08±0.13 dB and anti-squeezed quadrature at 9.29±0.13 dB by balanced homodyne measurement.

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