Researchers at Daegu Gyeongbuk Institute of Science and Technology (DGIST) in South Korea, in collaboration with the Korea Advanced Institute of Science and Technology (KAIST), have achieved a significant breakthrough in the integration of microelectromechanical systems (MEMS) into programmable photonic integrated circuits (PPICs). The study, published in the journal Nature Photonics, marks a major advancement in the field.

PPICs are designed to process light waves for computation, sensing, and signaling, offering programmable capabilities to meet diverse requirements. Sangyoon Han from the DGIST team highlights the potential of programmable photonic processors to outperform conventional supercomputers, providing faster, more efficient, and massively parallel computing. The use of light instead of electric current not only increases speed but also reduces power consumption and the size of PPICs, opening up possibilities for advancements in artificial intelligence, neural networks, quantum computing, and communications.

The heart of this breakthrough lies in integrating MEMS, tiny components capable of interconverting optical, electronic, and mechanical changes, onto PPIC chips with exceptionally low power requirements. The researchers claim to be the first to achieve this integration with silicon-based photonic MEMS technologies, significantly reducing power consumption to femtowatt levels, an improvement of over a million times compared to previous technology. The resulting technology can also be implemented on chips up to five times smaller than existing options.

The innovation in this research involves moving away from the dependence on temperature changes in dominant “thermo-optic” systems. Instead, the researchers utilize electrostatic forces—attractions and repulsions between fluctuating electric charges—to power the required tiny mechanical movements.

The integrated components on the chips manipulate the “phase” of light waves and control the coupling between different parallel waveguides, essential for building PPICs. These features, combined with micromechanical “actuators” or switches, create a fully programmable integrated circuit.

Crucially, the team’s innovative fabrication concepts for silicon-based parts are compatible with conventional silicon wafer technology, enabling large-scale production essential for commercial applications. The researchers plan to further refine their technology to develop and commercialize a photonic computer capable of outperforming conventional electronic computers in various applications, including artificial intelligence inference tasks, advanced image processing, and high-bandwidth data transmission. Han concludes with the expectation of pushing the boundaries of computational technology and contributing to the practical applications of photonics in modern technology.

By Impact Lab