Hybrid plasmonic nanodevices: Switching mechanism for the nonlinear emission

ANDREA V. BRAGAS; MAHI R. SINGH

AIP CONFERENCE PROCEEDINGS

AIP

Año: 2014 vol. 1590 p. 187 - 194

0094-243X

Control of the light emission at the nanoscale is of central interest in nanophotonics due to the manyapplications in very different fields, ranging from quantum information to biophysics. Resonant excitation of surfaceplasmon polaritons in metal nanoparticles create nanostructured and enhanced light fields around those structures, whichproduce their strong interaction in a hybrid nanodevice with other plasmonic or non-plasmonic objects. This interactionmay in turn also modulate the far field with important consequences in the applications. We show in this paper that thenonlinear emission from semiconductor quantum dots is strongly affected by the close presence of metal nanoparticles,which are resonantly excited. Using a pulsed laser, optical second harmonic is generated in the quantum dot, and it ishighly enhanced when the laser is tuned around the nanoparticle plasmon resonance. Even more interesting is thedemonstration of a switching mechanism, controlled by an external continuous-wave field, which can enhance orextinguish the SH signal, even when the pulsed laser is always on. Experimental observations are in excellent agreementwith the theoretical calculations, based on the dipole-dipole near-field coupling of the objects forming the hybrid system.