Invited talk: Laser science in a nanoscopic gap

Lasers have overcome numerous technological limitations in the 50 years since their first demonstration to become faster, brighter and smaller; however, scaling their size beyond the diffraction limit of light has only recently been achieved. Metal-based lasers can now create and sustain coherent light well below the diffraction limit, by generating and amplifying Surface Plasmon Polaritons, collective electron oscillations at metal-dielectric interfaces. In this talk, I will discuss our approach to constructing “plasmonic” lasers using semiconductor materials and outline some potential applications. Such devices could be the most efficient and compact method of delivering optical energy to the nanoscale. There are two benefits: firstly, the efficiently generated (focused) coherent laser field can be extremely intense; and secondly, vacuum fluctuations within the laser cavity are considerably stronger than in free space. Consequently, plasmonic lasers have the unique ability to drastically enhance both coherent and incoherent light-matter interactions bringing fundamentally new capabilities to bio-sensing, data storage, photolithography and optical communications. While there is a great deal of research to do on plasmonic laser systems, this talk highlights the feasibility of nano-scale light sources and the potential to do laser science at the nanoscale.