Second-order coherence properties of metallic nanolasers

Due to the high spontaneous emission coupled into the resonance mode in metallic nanolasers, there has been a debate concerning the coherence properties of this family of light sources. The second-order coherence function can unambiguously determine the nature of a given radiation. In this paper, an approach to measure the second-order coherence function for broad linewidth sources in the near-infrared telecommunication band is established based on a modified Hanbury Brown and Twiss configuration. Using this setup, it is shown that metallic coaxial and disk-shaped nanolasers with InGaAsP multiple quantum-well gain systems are indeed capable of generating coherent radiation. (C) 2016 Optical Society of America