Authors:	Yu-Hao Deng, Dobromil Respekta, Jing Bai, K. Molkens, Ezat Kheradmand, C. Pang, Robin R. Petit, Pepijn Verscheure, Philippe B. Green, Elaheh Teymouri, Christophe Detavernier, D. Van Thourhout, P. Geiregat, Zeger Hens
Title:	A Bifunctional Colloidal Quantum Dot Diode for Nanosecond Short-Wave Infrared Detection and Emission
Format:	International Journal
Publication date:	7/2026
Journal/Conference/Book:	Advanced Materials
Editor/Publisher:	Wiley,
Volume(Issue):	38(44) p.1-10
DOI:	10.1002/adma.74108
Citations:	Look up on Google Scholar
Download:	(1.7MB)

Abstract

Short-wave infrared (SWIR) technologies are vital for optical communication, all-weather imaging, and advanced spectroscopy. Using a single diode for light detection and emission can reduce device footprints, lower cost and enable fast, bidirectional communication. However, dual detection/emission operation often involves incompatible choices of material and stack design, which result in devices with inferior performance. Here, we introduce a bifunctional PbS QD diode stack that achieves, for the first time, nanosecond-fast photodetection and emission in a single SWIR device. Using thin active layers with high charge-carrier mobility and compact geometries, we demonstrate a record 2 ns response in photodiode (QDPD) mode and 11.7 ns rise time/6.5 ns fall time in light-emitting diode (QDLED) mode. This high-speed operation is combined with a 49% external quantum efficiency (EQE) and 2.6E12 cm Hz^0.5 W^−1 detectivity for QDPD operation, while the QDLED reaches 8.1% EQE. These high-speed, compact devices unify imaging and detection with a single, CMOS-compatible platform, and set the stage for integrated SWIR photonics and bidirectional optical interconnects. This work demonstrates the potential of QDs to unify imaging, detection, and communication in a single materials platform.