On-chip waveguide-integrated slot photodetector based on 2D material for high-speed optical interconnects

Photodetectors are critical building blocks in modern optical systems, enabling the conversion of light into electrical signals for applications ranging from high-speed communication to sensing and imaging. As data rates and integration demands increase, there is a growing need for photodetectors that combine high sensitivity, speed, and compact form factors. This talk will provide an overview of photodetector fundamentals and emerging material platforms, with a focus on advances using two-dimensional (2D) semiconductors. We highlight a recent demonstration of a MoTe₂-based slot waveguide photodetector, achieving a record gain-bandwidth product of 300 GHz through a transit-time-free and mobility-independent design. This architecture leverages long carrier lifetime, low dark current, and tight optical mode confinement to achieve both high speed and internal gain in an ultra-compact footprint. Such innovations open new pathways for scalable, high-performance photonic integrated circuits aimed at next-generation interconnects and signal processing.