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An ultra-sensitive pulsed balanced homodyne detector: Application to time-domain quantum measurements

H. Hansen·T. Aichele·C. Hettich·P. Lodahl·A. I. Lvovsky·J. Mlynek·S. Schiller
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Abstract

A pulsed balanced homodyne detector has been developed for precise measurements of electric field quadratures of pulsed optical quantum states. A high level of common mode suppression (> 85 dB) and low electronic noise (730 electrons per pulse) provide a signal to noise ratio of 14 dB for the measurement of the quantum noise of individual pulses. Measurements at repetition rates up to 1 MHz are possible. As a test, quantum tomography of the coherent state is performed and the Wigner function and the density matrix are reconstructed with a 99.5% fidelity. The detection system can also be used for ultrasensitive balanced detection in cw mode, e.g. for weak absorption measurements.

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H. Hansen, T. Aichele, C. Hettich, P. Lodahl, A. I. Lvovsky, J. Mlynek, S. Schiller. 2001-04-18. An ultra-sensitive pulsed balanced homodyne detector: Application to time-domain quantum measurements. https://doi.org/10.1364/ol.26.001714

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