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arXiv · 2204.09284

Spatially resolving amplitude and phase of light with a reconfigurable photonic integrated circuit

Johannes Bütow·Jörg S. Eismann·Maziyar Milanizadeh·Francesco Morichetti·Andrea Melloni·David A. B. Miller·Peter Banzer
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Abstract

Photonic integrated circuits (PICs) play a pivotal role in many applications. Particularly powerful are circuits based on meshes of reconfigurable Mach-Zehnder interferometers as they enable active processing of light. Various possibilities exist to get light into such circuits. Sampling an electromagnetic field distribution with a carefully designed free-space interface is one of them. Here, a reconfigurable PIC is used to optically sample and process free-space beams so as to implement a spatially resolving detector of amplitudes and phases. In order to perform measurements of this kind we develop and experimentally implement a versatile method for the calibration and operation of such integrated photonics based detectors. Our technique works in a wide parameter range, even when running the chip off the design wavelength. Amplitude, phase and polarization sensitive measurements are of enormous importance in modern science and technology, providing a vast range of applications for such detectors.

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Johannes Bütow, Jörg S. Eismann, Maziyar Milanizadeh, Francesco Morichetti, Andrea Melloni, David A. B. Miller, Peter Banzer. 2022-04-20. Spatially resolving amplitude and phase of light with a reconfigurable photonic integrated circuit. https://doi.org/10.1364/optica.458727

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