Low V_πL electro-optic switch based on a densely packed waveguide array phase shifter

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Lithium niobate on insulator (LNOI) and lithium tantalate on insulator (LTOI) are leading platforms for electro-optic (EO) switches.
• Achieving compact devices with low half-wave voltage-length product (VπL) is crucial for high-density integration but remains a challenge.

Purpose of the Study:

• To propose and experimentally demonstrate a novel low-VπL EO switch on x-cut LTOI.
• To overcome limitations in device size and voltage-length product for advanced photonic applications.

Main Methods:

• Design and fabrication of an EO switch utilizing a densely packed waveguide array (DPWA) phase shifter on x-cut LTOI.
• Experimental characterization of the device's VπL and insertion loss across a specific wavelength range.

Main Results:

• The demonstrated EO switch achieved a measured VπL of 1.49 V·cm, closely approximating the simulated value of 1.20 V·cm.
• Low insertion loss was maintained across the 1520-1580 nm wavelength band, indicating efficient optical performance.

Conclusions:

• The proposed DPWA phase shifter on LTOI is an effective approach for developing low-VπL EO switches.
• This advancement facilitates higher-density integration of EO devices for next-generation photonic systems.