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

TL;DR

This paper demonstrates a non-volatile optical phase shifter driven by a ferroelectric transistor, enabling multistate phase control with low power and CMOS compatibility, advancing large-scale programmable photonic integrated circuits.

Contribution

It introduces a novel hybrid MOS phase shifter driven by a ferroelectric FET, achieving multistate non-volatile phase shifts and proposing a scalable crossbar array architecture.

Findings

Achieved up to 1.25π phase shift with low switching energy (3.3 nJ).

Demonstrated CMOS-compatible operation voltages.

Validated selective write-in operation in a crossbar array architecture.

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.