Shortwave Infrared Polarization Imaging and Monolithic Integrated Polarization Amplification Systems Based on Aligned Carbon Nanotube Arrays

Abstract

Next‐generation shortwave infrared (SWIR) imaging systems generally require a multidimensional information sensing capability (including intensity, wavelength, polarization, phase, etc.), a highly integrated photodetector unit, and information processing, allowing for miniaturization and low‐cost production. However, traditional polarized SWIR imaging systems with integrated polarizer arrays as supplementary filters and silicon‐based amplifying circuits are complicated and very expensive. Here, a SWIR polarization‐sensitive photodetector and a monolithic integrated polarization amplification system (MIPAS) based on well‐aligned carbon nanotube (CNT) arrays are demonstrated. The polarization‐sensitive CNT photodetector exhibits anisotropic ratios of ≈5.18 and ≈7.56 at 1800 and 2000 nm wavelengths, respectively, and high‐resolution characteristics that can be utilized to image SWIR laser spots with a radius of less than 10 µm. Furthermore, MIPAS including a CNT field‐effect transistor, a CNT loading resistor, and a polarization‐sensitive CNT photodetector is used to increase the anisotropic ratio of the CNT photodetector. The amplified anisotropic ratio is improved up to 173 and 243 at 1800 and 2000 nm wavelengths, respectively, which is the maximum reported in the SWIR band. Our work demonstrates that the CNT polarization‐sensitive photodetector has the potential for SWIR polarization imaging with a monolithic integrated polarization amplification system.

Aligned Arrays of Semiconducting HiPCO SWCNTs Prepared by Liquid–Liquid Interface Confinement Self-Assembly for Optic–Electronic Applications

“…HiPCO SWCNT arrays can be active materials for (polarized) optoelectronics, electronics, and sensors. HiPCO SWCNTs exhibit a variety of chiralities, with a broad spectral absorption range that spans from ultraviolet to visible and near-infrared spectra, making them well-suited for optical applications, including but not limited to light emitters and photodetectors. − Aligned arrangement allows HiPCO SWCNTs to be used for polarizing optical devices. Additionally, HiPCO SWCNTs with small average diameters and large band gaps demonstrate outstanding switchable characteristics (on/off ratio) and significant potential for certain electronics .…”