Numerical analysis of nanowire surface recombination using a three-dimensional transient model

To characterize surface recombination of nanowires, time-resolved photoluminescence (TRPL) is commonly implemented to correlate measured lifetime with the nonradiative effect at surface. In this work, we develop a three-dimensional transient model to perform a numerical analysis of surface recombination for InGaAs nanowires on GaAs substrates. By mimicking a complete TRPL measurement process, we computationally calculate optical generation and emission of InGaAs nanowires, and numerically probe the carrier dynamics inside nanowires. It is found that the TRPL spectra are determined by a complex convolution of surface recombination velocity and incident wavelengths. In addition, we show that due to the three-dimensional geometry of nanowire, using a typical analytical equation to extract surface recombination velocity might be no longer valid. We believe these results provide an alternative approach for the computational analysis of TRPL measurements and surface properties for three-dimensional nanostructured devices.