Non-volatile hybrid optical phase shifter driven by a ferroelectric transistor

Rui Tang; Kouhei Watanabe; Masahiro Fujita; Hanzhi Tang; Tomohiro Akazawa; Kasidit Toprasertpong; Shinichi Takagi; Mitsuru Takenaka

doi:10.1002/lpor.202300279

arXiv · 2210.06979

Non-volatile hybrid optical phase shifter driven by a ferroelectric transistor

Rui Tang·Kouhei Watanabe·Masahiro Fujita·Hanzhi Tang·Tomohiro Akazawa·Kasidit Toprasertpong·Shinichi Takagi·Mitsuru Takenaka

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Abstract

Optical phase shifters are essential elements in photonic integrated circuits (PICs) and function as a direct interface to program the PIC. Non-volatile phase shifters, which can retain information without a power supply, are highly desirable for low-power static operations. Here a non-volatile optical phase shifter is demonstrated by driving a III-V/Si hybrid metal-oxide-semiconductor (MOS) phase shifter with a ferroelectric field-effect transistor (FeFET) operating in the source follower mode. Owing to the various polarization states in the FeFET, multistate non-volatile phase shifts up to 1.25{\pi} are obtained with CMOS-compatible operation voltages and low switching energy up to 3.3 nJ. Furthermore, a crossbar array architecture is proposed to simplify the control of non-volatile phase shifters in large-scale PICs and its feasibility is verified by confirming the selective write-in operation of a targeted FeFET with a negligible disturbance to the others. This work paves the way for realizing large-scale non-volatile programmable PICs for emerging computing applications such as deep learning and quantum computing.

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Rui Tang, Kouhei Watanabe, Masahiro Fujita, Hanzhi Tang, Tomohiro Akazawa, Kasidit Toprasertpong, Shinichi Takagi, Mitsuru Takenaka. 2022-10-12. Non-volatile hybrid optical phase shifter driven by a ferroelectric transistor. https://doi.org/10.1002/lpor.202300279

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