Colloquium: Garnett Bryant
Wednesday, March 23, 2016 · 3:30 - 4:30 PM
TITLE: Approaching the quantum limit for nanoplasmonics
ABSTRACT: Nanoplasmonics in metallic nanosystems has been intensely studied for the last 20 years. In particular, using nanoplasmonics to confine light near metal surfaces in nanoscale volumes has opened a wide range of new applications for nano-optics including bio and chemical sensing down to the single-molecule level, engineered metamaterials, and enhanced light conversion for solar collection. Classical optical physics (Maxwell’s equations and the material’s bulk dielectric function) usually provides an excellent description for nanoplasmons. In optics, meanwhile, quantum effects have been known for years and have spawned the field of quantum optics. Whether, when or how quantum effects should be important for nanoplasmons has not been obvious because, unlike photons, plasmons decay in femtoseconds, leaving little time for quantum effects to play out. However, recently it has become clear that quantum effects can be important and that quantum optics with nanoplasmons is possible. Several examples are discussed here to show the need for a quantum description of nanoplasmonics. To better understand the quantum character of nanoplasmons, we use time-dependent density functional theory and simple, exactly solvable models, to study plasmons in small metallic spheres and linear atomic chains. Results are presented to show what can be learned about quantum plasmons in nano-scale and atomic scale systems.
ABSTRACT: Nanoplasmonics in metallic nanosystems has been intensely studied for the last 20 years. In particular, using nanoplasmonics to confine light near metal surfaces in nanoscale volumes has opened a wide range of new applications for nano-optics including bio and chemical sensing down to the single-molecule level, engineered metamaterials, and enhanced light conversion for solar collection. Classical optical physics (Maxwell’s equations and the material’s bulk dielectric function) usually provides an excellent description for nanoplasmons. In optics, meanwhile, quantum effects have been known for years and have spawned the field of quantum optics. Whether, when or how quantum effects should be important for nanoplasmons has not been obvious because, unlike photons, plasmons decay in femtoseconds, leaving little time for quantum effects to play out. However, recently it has become clear that quantum effects can be important and that quantum optics with nanoplasmons is possible. Several examples are discussed here to show the need for a quantum description of nanoplasmonics. To better understand the quantum character of nanoplasmons, we use time-dependent density functional theory and simple, exactly solvable models, to study plasmons in small metallic spheres and linear atomic chains. Results are presented to show what can be learned about quantum plasmons in nano-scale and atomic scale systems.