In this work, we study the optical emission from arrays of InGaN/GaN MQW nanofin and nanorod arrays with sizes ranging from a few micrometers down to sub-wavelength dimensions (i.e., nanometers). Such systems are of interest for developing arrays of single addressable nanoLEDs, which could be used to obtain a visible wavelength super-resolution microscope where the resolution is due to highly localized light spots with sub-wavelength LED-to-LED pitch.
We have used commercial full-wave Maxwell solvers (COMSOL, CST) to calculate the optical field emitted from a single nanoLED in a periodic array for a wavelength of 450 nm. Simulations on 11×11 nanoLED arrays with pitches of 200 nm up to 800 nm and diameters of down to 50 nm have been conducted, in which the dependency of the emission pattern on different structural parameters is studied. In case of small nanoLED array with very narrow pitch, a large optical cross-talk between the activated LED and its neighboring pixels was found. Moreover, in presence of cross-talks, test objects smaller than the LED pitch placed on its surface with influence of near field could potentially be resolved by evaluating the varied emission patterns obtained by different pixel activations. Routes to achieve higher localized optical fields and reduce optical cross-talk have been also investigated by modifying the nanoLED array structures (e.g., by introducing filling material among the LED pixels).