Abstract
Hybrid heterostructures are pivotal in the advanced broadband detection technology. The emergence of 2D semimetals has expanded the range of materials in heterostructures beyond conventional narrow-gap materials for room-temperature broadband detection applications due to their extraordinary optical and electrical properties. This review outlines the cutting-edge and latest advancements in broadband photodetectors (PDs) engineered from heterostructures that synergistically combine 2D semimetals with several different dimensional materials. It begins with a fundamental investigation, offering an in-depth explanation of the essential material properties and a summary of synthesis methodologies. Then, the discussion advances to provide an analytical overview of the categorization, underlying photodetection mechanism, and figures-of-merit of these advanced PDs. Subsequently, the narrative shifts to a comprehensive analysis of heterogeneous integrated devices. The review further highlights the diverse optoelectronic applications of broadband PDs, spanning image sensing, optical communication, position-sensitive detection, integrated sensing and computing, spintronics, and computational spectroscopy are thoroughly highlighted. Finally, the review concludes by addressing the challenges and opportunities in advancing 2D semimetal materials for photodetection.