Direction reconfigurable non-reciprocal acousto-optic modulator on chip

Donggyu B Sohn; Gaurav Bahl

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arXiv · 1908.02382

Direction reconfigurable non-reciprocal acousto-optic modulator on chip

Donggyu B Sohn·Gaurav Bahl

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Abstract

Non-reciprocal components are essential in photonic systems for protecting light sources and for signal routing functions. Acousto-optic methods to produce non-reciprocal devices offer a foundry-compatible alternative to magneto-optic solutions and are especially important for photonic integration. In this paper, we experimentally demonstrate a dynamically reconfigurable non-reciprocal acousto-optic modulator at telecom wavelength. The modulator can be arranged in a multitude of reciprocal and non-reciprocal configurations by means of an external RF input. The dynamic reconfigurability of the device is enabled by a new cross-finger interdigitated piezoelectric transducer that can change the directionality of the reciprocity-breaking acoustic excitation based on the phase of the RF input. The methodology we demonstrate here may enable new avenues for direction dependent signal processing and optical isolation.

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Donggyu B Sohn, Gaurav Bahl. 2019-08-06. Direction reconfigurable non-reciprocal acousto-optic modulator on chip. https://arxiv.org/abs/1908.02382

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