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arXiv · 0704.1918

Quantum Filtering of Optical Coherent States

C. Wittmann·D. Elser·U. L. Andersen·R. Filip·P. Marek·G. Leuchs
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Abstract

We propose and experimentally demonstrate non-destructive and noiseless removal (filtering) of vacuum states from an arbitrary set of coherent states of continuous variable systems. Errors i.e. vacuum states in the quantum information are diagnosed through a weak measurement, and on that basis, probabilistically filtered out. We consider three different filters based on on/off detection phase stabilized and phase randomized homodyne detection. We find that on/off etection, optimal in the ideal theoretical setting, is superior to the homodyne strategy in a practical setting.

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C. Wittmann, D. Elser, U. L. Andersen, R. Filip, P. Marek, G. Leuchs. 2008-09-29. Quantum Filtering of Optical Coherent States. https://doi.org/10.1103/physreva.78.032315

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