Author(s): Liu, XN (Liu, Xiaona); Kongsuwan, N (Kongsuwan, Nuttawut); Li, XG (Li, Xiaoguang); Zhao, DX (Zhao, Dongxing); Wu, ZM (Wu, Zhengmao); Hess, O (Hess, Ortwin); Zhang, XH (Zhang, Xinhui)

Source: JOURNAL OF PHYSICAL CHEMISTRY LETTERS Volume: 10 Issue: 24 Pages: 7594-7602 DOI: 10.1021/acs.jpclett.9b02627 Published: DEC 19 2019

Abstract: Semiconductor-metal hybrid nanostructures present an exotic class of nonlinear optical materials due to their potential optoelectronic applications. However, most studies to date focus on their total optical responses instead of contributions from individual nonlinear orders. In this Letter, we present a theoretical study on the third-order nonlinear optical absorption of a hybrid colloidal semiconductor quantum dot (SQD)-metal nanoparticle (MNP) system. We develop a novel analytic treatment based on the nonlinear density matrix equation and derive a closed-form expression for the optical susceptibility. Our. study identifies the parameter space that governs the system's optical transition from being a saturable absorber to a Fano-enhanced absorber. We attribute this transition to the plasmon-mediated self-interaction of the SQD. The findings provide a valuable guideline for optimized designs of functional nanophotonic devices based on SQD-MNP hybrid structures.

Accession Number: WOS:000503919300008

PubMed ID: 31769991

Author Identifiers:

Author        Web of Science ResearcherID        ORCID Number

Kongsuwan, Nuttawut                  0000-0002-8037-3100

Hess, Ortwin                  0000-0002-6024-0677

ye, jialiang                  0000-0002-5888-3841

ISSN: 1948-7185

Full Text: https://pubs.acs.org/doi/10.1021/acs.jpclett.9b02627