“Binary Materials” for Photodetection from Mid-Infrared, Visible, to X-ray

Light-matter interaction is a long-lasting theme in condensed matter physics and optoelectronics. Light detection in different wavelength regimes is the foundation of a wide range of sensing, imaging, medical and surveillance technologies. In this talk I will discuss the use of transition-metal oxides, hybrid organo-metal perovskites and other nanomaterials in “binary” mixed-dimensional heterostructures with proper bandgaps and architectures to detect photons with different wavelengths. First, for visible light detection, we demonstrate that combining 3D hybrid perovskites with high-mobility 1D carbon nanotubes or 2D two-dimensional metal dichalcogenides significantly enhances charge transport and device performance [1,2]. Second, we report a mid-infrared (up to 10 um) mixed-dimensional photodetector enabled via coupling graphene with a narrow bandgap semiconductor Ti2O3 [3]. Finally, using epitaxial ferroelectric/semiconductor oxide junctions with a current-perpendicular-to-plane geometry, we achieve a new type of X-ray detector with colossal persistent X-ray-induced photoconductivity [4].1.F. Li, et al., Advanced Materials, 2017, 29, 1602432.2.C. Ma, et al., Advanced Materials, 2016, 28, 3683.3.X. Yu, et al., Nature Communications, 2018, 9, 4299.4.W. J. Hu, et al., Advanced Functional Materials, 2018, 28, 1704337.