Thermo-optical switch with wavelength division multiplexing function.

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Telecommunications Technology

Background:

• Compact and flexible optical switches are crucial for advancing optical communication networks.
• Integrating multiple functionalities, such as wavelength division (de)multiplexing (WDM) and routing, into a single device is a key challenge.

Purpose of the Study:

• To propose and experimentally demonstrate a novel thermo-optical switch with integrated WDM capabilities.
• To achieve simultaneous wavelength separation and optical path reconfiguration in a compact device.

Main Methods:

• The switch design utilizes a 1x2 Bezier multimode interferometer (MMI) and an angled multimode interferometer (AMMI).
• The device is fabricated on a silica platform with a 2% refractive index difference.
• Thermo-optic effect is employed for controlling the optical path and wavelength separation.

Main Results:

• The demonstrated switch successfully separates 1490 nm and 1550 nm wavelengths and reconfigures optical paths.
• Achieved performance metrics include excess loss < 1.2 dB, crosstalk < -21.7 dB, extinction ratio > 21.7 dB, and 3 dB bandwidth > 30.8 nm.
• Switching times are rapid (0.88 ms rise, 0.94 ms fall) with a power consumption of 246.6 mW.

Conclusions:

• The developed thermo-optical switch effectively combines WDM and routing functions in a compact footprint (13.63 × 0.385 mm²).
• The device exhibits excellent optical performance, including low loss, high extinction ratio, and wide bandwidth.
• Its scalable design holds promise for constructing large port-count optical switches for future communication systems.