Optical extinction spectra were measured for dispersions of germanium (Ge) nanorods produced by arrested solution-liquid-solid (SLS) growth using bismuth (Bi) seeds. Peaks in the real (n) and imaginary (k) parts of the complex index of refraction of Ge give rise to an absorbance peak at ∼600 nm, which shifts to slightly longer wavelengths with increased aspect ratio. Discrete dipole approximation calculations of absorption and scattering cross sections reveal that the length-dependent optical properties result from enhanced light trapping and absorption.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films