Colloidal Quantum‐Dot Heterojunction Imagers for Room‐Temperature Thermal Imaging

Abstract

Abstract Room‐temperature operation or high‐operation temperature (HOT) is essential for mid‐wave infrared (MWIR) optoelectronics devices providing low‐cost and compact systems for numerous applications. Colloidal quantum dots (CQDs) have emerged as a rising candidate to enable photodetectors to operate at HOT or room temperature and develop the next‐generation infrared focal plane array (FPA) imagers. Here, band‐engineered heterojunctions are demonstrated to suppress dark current with well‐passivated mercury telluride (HgTe) CQDs enabling room‐temperature MWIR imaging by single‐pixel scanning and 640 × 512 FPA sensitive thermal imaging above 250 K. As a result, the room‐temperature detectivity reaches as high as 1.26 × 10 10 Jones, and the noise equivalent temperature difference ( NETD ) is as good as 25 mK up to 200 K.