title: Far-field measurement of ultra-small plasmonic mode volume.
abstract: Light-matter interaction can be greatly enhanced in nano-scale plasmonic cavities with tightly confined optical mode, where the mode volume determines the interaction strength. The experimental determination of the mode volume of plasmonic elements is therefore of fundamental importance. Mapping the electric field distribution using near-field scanning optical microscopy (NSOM) may disturb the field distribution hence prevent a reliable measurement of the mode volume. Here, we develop a non-pertubative technique to experimentally determine the mode volume of plasmonic resonators in the far field through a unique optical force method.
authors.affiliation: Nanoscale Science and Engineering Center, 3112 Etcheverry Hall, University of California,Berkeley, California 94720, USA.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhang
authors.forename: Yong-Shik
authors.initials: YS
authors.lastname: Park
authors.forename: Yongmin
authors.initials: Y
authors.lastname: Liu
authors.forename: Thomas
authors.initials: T
authors.lastname: Zentgraf
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
mesh_terms: D003198:Computer Simulation; D008962:Models, Theoretical; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D020349:Surface Plasmon Resonance / Q000379:methods*