Enhanced emission from ultra-thin long wavelength infrared superlattices on epitaxial plasmonic materials

摘要

Molecular beam epitaxy allows for the monolithic integration of wavelength-flexible epitaxial infrared plasmonic materials with quantum-engineered infrared optoelectronic active regions. We experimentally demonstrate a sixfold enhancement in photoluminescence from ultrathin (total thickness lambda(o)/33) long wavelength infrared (LWIR) superlattices grown on highly doped semiconductor "designer metal" virtual substrates when compared to the same superlattice grown on an undoped virtual substrate. Analytical and numerical models of the emission process via a dyadic Green's function formalism are in agreement with experimental results and relate the observed enhancement of emission to a combination of Purcell enhancement due to surface plasmon modes as well as directionality enhancement due to cavity-substrate-emitter interaction. The results presented provide a potential pathway toward efficient, ultrasubwavelength LWIR emitter devices, as well as a monolithic epitaxial architecture offering the opportunity to investigate the ultimate limits of light-matter interaction in coupled plasmonic/optoelectronic materials. Published under license by AIP Publishing.