A filterless organic photodetector electrically switchable between visible and infrared detection
Ning Li, Naresh Eedugurala, Jason D. Azoulay, Tse Nga Ng
Abstract
Wavelength tunable detectors are essential for capturing spectral information within diverse applications such as those related to object recognition and identification. Here, we present a generalizable design for a compact dual-band photodetector based on the integration of two back-to-back organic photodiodes that respond to visible (400–700 nm) and infrared light (700–1,400 nm). The polarity under external bias provides the electronic switch between visible and infrared detection modes. Operating at a low voltage of <1 V, the organic photodetector exhibits a fast response with a −3-dB cutoff frequency of 18 kHz and specific detectivity of 7.8 × 109 Jones. The device provides contactless measurements of high temperatures that originated from blackbody radiation and spectroscopic dual-band imaging for object identification.