Diode Laser Mode Selection via Periodic Arrays of Adjacent Nanoscale Metallic Structures

The dominant lasing modes of a InAs quantum dot GaAs/AlGaAs edge emitting bar lasers are demonstrated to be sensitive to periodic arrays of Au nanostructures along the edges of the laser cavity. It is postulated that the array introduces losses to all of the modes that do not have the same period as the array, thus favoring one that is least lossy. Estimates of the strength of the interaction between the laser and nanostructures are presented to justify this hypothesis. Only small changes in threshold current are observed with the presence of the nanostructures, but this is consistent with the postulated strength of the interaction between the laser and the nano structures.