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arXiv · 1309.2980

High Fidelity Detection of the Orbital Angular Momentum of Light by Time Mapping

Abstract

We demonstrate high-fidelity detection of the orbital angular momentum (OAM) of light using a compact and practical OAM spectrometer that maps the OAM spectrum to time. The spectrometer consists of a single optical delay loop to achieve timing mapping, a vortex phase plate that iteratively decreases the OAM value, and a single mode fibre to distinguish zero from non-zero OAM states. Light with arbitrarily OAM compositions can be measured. For light with OAM up to 4hbar, we measured an average crosstalk of -21.3 dB, which is mainly limited by the purity of the input states and optical alignment.

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Paul Bierdz, Minho Kwon, Connor Roncaioli, Hui Deng. 2014-01-11. High Fidelity Detection of the Orbital Angular Momentum of Light by Time Mapping. https://doi.org/10.1088/1367-2630%2F15%2F11%2F113062

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