Keele Research Repository

We report on the tuning of the spectral response of superlattice (SL) diodes based on dilute nitride Ga(AsN) alloys by post-growth hydrogenation. Hydrogen is incorporated into the superlattice where it neutralizes the electronic activity of nitrogen by forming N-H complexes. We exploit the controlled thermal dissociation of the complexes to tune the energy of the SL photocurrent absorption and electroluminescence emission; also, by annealing a submicron spot with a focused laser beam we create a preferential path for the injection of carriers, thus activating a nanoscale light emitting region. This method can be used for fabricating planar diode arrays with distinct optical active regions, all integrated onto a single substrate.

This work was supported by the University of Nottingham, the EU (under Grant Agreement No. PIEF-GA-2010-272612), the Italian MIUR (under FIRB 2012 project DeLIGHTeD, prot. RBFR12RS1W), and the EPSRC. We acknowledge useful discussions with Professor Mario Capizzi and Professor Antonio Polimeni (Sapienza Università di Roma).