External optical feedback effects in electrically pumped semiconductor nano-laser arrays

Detailed simulations have been undertaken of the dynamical response of linear and triangular arrays of nano-lasers to external optical feedback from a common external mirror. Careful attention is given to forms of dynamics that arise in such devices when experimentally accessible parameters such as the optical feedback strength, laser bias current, and external cavity length are changed – including for the latter on wavelength scales. In addition, the role played by the strength of the coupling between the nano-lasers is indicated. A salient feature of nano-lasers is the possibility of enhanced spontaneous emission via the Purcell effect and its impact on obtainable dynamics is illustrated. In general, the elements of the arrays display a combination of stable, periodic, quasi-periodic, and chaotic behaviour. Prospects for significant generalizations of the analysis undertaken here are briefly addressed.