Ultrafast reversal of a Fano resonance in a plasmon-exciton system

Thumbnail Image

Files

PhysRevB.88.075411.pdf (1.75 MB)
Supplementary-Materials.pdf (2.32 MB)

Links to Files

https://journals.aps.org/prb/abstract/10.1103/PhysRevB.88.075411

Permanent Link

https://doi.org/10.1103/PhysRevB.88.075411
 http://hdl.handle.net/11603/29189

Collections

UMBC Physics Department

Author/Creator

Author/Creator ORCID

https://orcid.org/0000-0002-6370-8765

Date

2013-08-12

Type of Work

journal articles
Text

Department

Program

Citation of Original Publication

Shah, Raman A., Norbert F. Scherer, Matthew Pelton, and Stephen K. Gray. “Ultrafast Reversal of a Fano Resonance in a Plasmon-Exciton System.” Physical Review B 88, no. 7 (August 12, 2013): 075411. https://doi.org/10.1103/PhysRevB.88.075411.

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0

Subjects

Abstract

When a two-level quantum dot and a plasmonic metal nanoantenna are resonantly coupled by the electromagnetic near-field, the system can exhibit a Fano resonance, resulting in a transparency dip in the optical spectrum of the coupled system. We calculate the nonlinear response of such a system, for illumination both by continuous-wave and ultrafast pulsed lasers, using both a cavity quantum electrodynamics and a semiclassical coupled-oscillator model. For the experimentally relevant case of thermal broadening of the quantum-dot transition (to meV values consistent with ∼100 K), we predict that femtosecond pulsed illumination can lead to a reversal of the Fano resonance, with the induced transparency changing into a superscattering spike in the spectrum. This ultrafast reversal is due to a transient change in the phase relationship between the dipoles of the plasmon and exciton. It thus represents a new approach to dynamically control the collective optical properties and coherence of coupled nanoparticle systems.