A Non-Volatile Tunable Ultra-Compact Silicon Photonic Logic Gate

Area of Science:

• Photonics and Optoelectronics
• Materials Science
• Integrated Circuits

Background:

• Logic gates are fundamental components in electronic integrated circuits (EICs) and are crucial for photonic integrated circuits (PICs).
• Existing optical logic gates often lack non-volatile characteristics, tunability, or are not ultra-compact, hindering seamless integration with EICs.

Purpose of the Study:

• To propose and demonstrate a novel non-volatile, ultra-compact all-photonics logic gate.
• To utilize the unique phase change properties of optical phase change materials (O-PCMs) for logic gate functionality.
• To achieve integration of photonic and electronic circuits at the chip scale.

Main Methods:

• Designed an all-photonics logic gate with an ultra-compact footprint of 2 μm × 2 μm.
• Employed antimony selenide (Sb₂Se₃) as the optical phase change material.
• Regulated the phase transition (crystalline or amorphous states) of Sb₂Se₃ to control the logic gate's function (XOR or AND).

Main Results:

• The device demonstrated non-volatile operation, functioning as either an XOR or an AND gate based on the Sb₂Se₃ material state.
• Achieved high logic contrasts: 11.8 dB for logic '1' and 5.7 dB for logic '0' at a wavelength of 1550 nm.
• The fabricated logic gate boasts an ultra-small footprint, non-volatile characteristics, and tunability.

Conclusions:

• The proposed ultra-compact, non-volatile all-photonics logic gate meets the requirements for integrating PICs and EICs.
• This technology enables the development of truly chip-scale optoelectronic logic solutions.
• The use of O-PCMs offers a promising pathway for advanced photonic computing components.