Environment-dependent optical scattering of cuprous oxide microcrystals in liquid dispersions and Langmuir–Blodgett films

Abstract

Optical properties of semiconductor materials are important for their broad applications, especially when the materials are nano- and micrometer crystals. Here we show that cuprous oxide microcrystals have three extinction peaks that are environment sensitive in the visible-near infrared region. The extinction peaks show a linear blue shift with the increase in refractive index of the surrounding medium. The environment-dependent shift of extinction spectra can also be observed for cuprous oxide in cast films and Langmuir–Blodgett films. The sensitivity of environment-dependent optical behavior depends on the energy of the extinction peaks. Both experimental work and theoretical calculation on the environment-dependent spectra of cuprous oxide microcrystals provide valuable knowledge on these functional semiconductor materials for various applications.