Compound optical crosspoint with low crosstalk.

Area of Science:

• Photonics and optical engineering.
• Materials science of electro-optic materials.

Background:

• Developing high-isolation optical switches is essential for complex integrated photonic circuits.
• Lithium Tantalate (LiTaO3) is a suitable material for electro-optic devices due to its properties.

Purpose of the Study:

• To experimentally demonstrate a novel multimode electro-optical switch.
• To achieve high isolation between channels in the switch.
• To assess the feasibility of integrating the switch into optical matrices.

Main Methods:

• Fabrication of a 70-microm-thick Z-cut LiTaO3 plate.
• Design and implementation of a four-port fiber-compatible optical switch.
• Utilizing an in-plane crossover, two optical switches, and a curved waveguide for the crosspoint.
• Applying 450-V DC for optical switching control.

Main Results:

• Successful experimental demonstration of the multimode electro-optical switch.
• Achieved high isolation between channels.
• Observed 10% light transfer into the cross-channel for convergent input light (NA=0.07).
• Measured an optical switching ratio of 26 dB for the cross-channel.

Conclusions:

• The demonstrated LiTaO3 electro-optical switch meets the requirement for high channel isolation.
• The fiber-compatible design is suitable for integration into optical matrices.
• The device shows promise for applications in optical switching and signal routing.