Nonreciprocal components are essential in photonic systems for protecting light sources and for signal routing functions. Acousto-optic methods to produce nonreciprocal 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 nonreciprocal acousto-optic modulator at the telecom wavelength with a peak contrast of 8 dB and a 3 dB bandwidth of 1.1 GHz. The modulator can be arranged in a multitude of reciprocal and nonreciprocal 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.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Computer Networks and Communications