Photoluminescence of single gold nanorods following nonlinear excitation
Abstract
The photoluminescence (PL) mechanisms of gold nanorods following nonlinear excitation are described. Using single-particle nonlinear optical measurements, we compare PL signals resulting from both the plasmon-resonant and non-resonant excitations. In both cases, spectrally broad interband PL emission was observed. However, we also show that resonant excitation of the longitudinal plasmon mode leads to an increased photonic density of states at energies corresponding to the transverse plasmon resonance. This increased density of states is achieved by a multi-step mechanism, which is initiated by three-photon excitation and followed by an Auger relaxation process. Importantly, the results show that nonlinear excitation can lead to energy and polarization modulation of nanoparticle optical signals that are not observed using linear excitation. This work also demonstrates the effectiveness of single-nanoparticle PL studies for understanding how plasmon-resonant excitations can be used to modify hot carrier distributions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 12, 2020
- Source ID
- 10.1063/5.0021388
Entities
People
- Kenneth L. Knappenberger
- Kyoungweon Park
- Richard A. Vaia
- Tian Zhao
- Zehua Li
Organizations
- Air Force Office of Scientific Research
- Air Force Research Laboratory
- National Science Foundation
- Pennsylvania State University