Compact nonvolatile 2×2 photonic switch based on two-mode interference.

Area of Science:

• Photonics and Optical Engineering
• Materials Science
• Integrated Circuits

Background:

• Phase change materials (PCMs) enable nonvolatile photonic switches for power-efficient programmable photonic integrated circuits.
• Conventional PCMs like Ge2Sb2Te5 suffer from high insertion loss and large footprints due to absorption loss with silicon waveguides.
• There is a need for novel materials and waveguide structures to overcome these limitations.

Purpose of the Study:

• To propose and demonstrate a novel 2x2 photonic switch design.
• To utilize ultralow loss Sb2S3 integrated within a multimode slot waveguide (MSW).
• To achieve high performance with low insertion loss and crosstalk for compact photonic devices.

Main Methods:

• Integration of Sb2S3 within the slot region of a multimode slot waveguide (MSW) supporting TE00 and TE01 modes.
• Exploitation of the phase change property of Sb2S3 to tune two-mode interference.
• Design and simulation of a hybrid Sb2S3-MSW section for light transmission control.

Main Results:

• A compact ∼9.4 µm-long Sb2S3-MSW section effectively switches light between bar and cross ports.
• Achieved insertion loss (IL) < 0.26 dB and crosstalk (CT) < -13.6 dB in the telecommunication C-band.
• Demonstrated exceptional performance at 1550 nm with CT of -36.1 dB (amorphous) / -31.1 dB (crystalline) and IL of 0.073 dB / 0.055 dB.

Conclusions:

• The proposed Sb2S3-based photonic switch offers a compact and efficient solution for integrated photonics.
• The enhanced electric field in the slot region boosts interaction with Sb2S3, enabling low-loss switching.
• This technology holds promise for reconfigurable photonic devices and power-efficient programmable photonic integrated circuits.