Integrated O- and C-band Silicon-Lithium Niobate Mach-Zehnder Modulators with 100 GHz Bandwidth, Low Voltage, and Low Loss

TL;DR

This paper presents a hybrid silicon-lithium niobate Mach-Zehnder modulator capable of operating over both O- and C-bands with 100 GHz bandwidth, low voltage, and minimal optical loss, suitable for advanced optical communication.

Contribution

The work introduces a simplified fabrication process for broadband TFLN electro-optic modulators covering both O- and C-bands on a single chip, with high bandwidth and low voltage operation.

Findings

Achieved 100 GHz EO bandwidth in both wavelength bands.

Realized low on-chip optical loss in O- and C-bands.

Demonstrated low VπL figure-of-merit (~2-3 V·cm).

Abstract

Broadband integrated thin-film lithium niobate (TFLN) electro-optic modulators (EOM) are desirable for optical communications and signal processing in both the O-band (1310 nm) and C-band (1550 nm). To address these needs, we design and demonstrate Mach-Zehnder (MZ) EOM devices in a hybrid platform based on TFLN bonded to foundry-fabricated silicon photonic waveguides. Using a single silicon lithography step and a single bonding step, we realize MZ EOM devices which cover both wavelength ranges on the same chip. The EOM devices achieve 100 GHz EO bandwidth (referenced to 1 GHz) and about 2-3 V$.$cm figure-of-merit ($V_\pi L$) with low on-chip optical loss in both the O-band and C-band.