Because carbon nanotube (CNT) films have high photothermal conversion efficiency (PTCE), they have been widely used in bolometric and photothermoelectric photodetectors, seawater desalination, and cancer therapy. Here, we present a simple, quick, and non-destructive method to measure the PTCE of CNT films. According to the linear relationship between the Raman shift of the G+ peak and the temperature of a CNT, the offset of the G+ peak under varying excitation light power can characterize the changed temperature. Combining the simulation of the temperature distribution, the final value of the PTCE can be obtained. Finally, a CNT film with a high PTCE was chosen to be fabricated as a bolometric photodetector; a quite high responsivity (2 A W−1 at 532 nm) of this device demonstrated the effectiveness of our method.

A comprehensive understanding of the optical properties of atmospheric aerosol is essential for a variety of applications, such as optical imaging, optical communication, and remote sensing. In recent years, many theories and numerical simulation methods have been developed to connect aerosol physicalchemical properties to their intrinsic and integral optical properties. Usually, simulations and measurements are intertwined to synergistically attain the retrieval of aerosol optical properties and mitigate or even eliminate the adverse impacts of aerosol during imaging, sensing, or communication. This review covers the fundamental theories of aerosol optical properties, the development of numerical simulations, the instrumentbased sampling measurements, and the cutting-edge techniques of remote sensing. Numerical simulations have been progressing from symmetric particles to asymmetric particles over the past two decades, although any simulation method is limited by specific shape and a restricted size parameter range. Thus, this review also examines the most typical advances in aerosol instrumentation that are frequently used to measure the intrinsic optical properties of unknown aerosols. Such obtained properties validate simulations and constitute the basis of integral optical properties. In terms of practical applications, integral optical properties are the most critical knowledge about atmospheric aerosol. Remote sensing measurements, be it ground-based, airborne, or satellite-based, all retrieve integral optical properties of atmospheric aerosol from various perspectives, which are elaborated upon in this review. In conclusion, this review provides an allencompassing comprehension of aerosol optical properties.