A wideband balanced homodyne detector for high speed continuous variable quantum key distribution systems
نویسندگان
چکیده
In Gauissian-modulated coherent-state quantum key distribution, the measurement of quadratures of coherent states is performed by using homodyne detector. However, the existing detectors usually suffer from narrow band. Here we present a method to design a high-speed shot-noise-limited balanced homodyne detector. A 300 MHz bandwidth detector was experimentally tested and the level of shot noise is 14 dB higher than the electronic noise. The results show that a detector with this method is potential to design a GHz bandwidth detector for continuous variable quantum key distribution at a low level of shot noise to electronic noise ratio.
منابع مشابه
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