We present a computational study on the anisotropic luminescence and the efficiency of a core-shell type nanowire
LED based on GaN with InGaN active quantum wells. The physical simulator used for analyzing this device
integrates a multidimensional drift-diffusion transport solver and a k · p Schr¨odinger problem solver for quantization
effects and luminescence. The solution of both problems is coupled to achieve self-consistency. Using this
solver we investigate the effect of dimensions, design of quantum wells, and current injection on the efficiency and
luminescence of the core-shell nanowire LED. The anisotropy of the luminescence and re-absorption is analyzed
with respect to the external efficiency of the LED. From the results we derive strategies for design optimization.