Quantum plasmon enhanced nonlinear wave mixing in graphene nanoflakes  

作　　者：Hanying Deng Changming Huang Yingji He Fangwei Ye 邓寒英;黄长明;何影记;叶芳伟(School of Photoelectric Engineering,Guangdong Polytechnic Normal University,Guangzhou 510665,China;Department of Electronic Information and Physics,Changzhi University,Changzhi 046011,China;School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]School of Photoelectric Engineering,Guangdong Polytechnic Normal University,Guangzhou 510665,China [2]Department of Electronic Information and Physics,Changzhi University,Changzhi 046011,China [3]School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Chinese Physics B》2021年第4期97-105,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11947007);the Natural Science Foundation of Guangdong Province,China(Grant No.2019A1515011499);the Department of Education of Guangdong Province,China(Grant No.2019KTSCX087)。

摘　　要：A distant-neighbor quantum-mechanical method is used to study the nonlinear optical wave mixing in graphene nanoflakes(GNFs),including sum-and difference-frequency generation,as well as four-wave mixing.Our analysis shows that molecular-scale GNFs support quantum plasmons in the visible spectrum region,and significant enhancement of nonlinear optical wave mixing is achieved.Specifically,the second-and third-order wave-mixing polarizabilities of GNFs are dramatically enhanced,provided that one(or more) of the input or output frequencies coincide with a quantum plasmon resonance.Moreover,by embedding a cavity into hexagonal GNFs,we show that one can break the structural inversion symmetry and enable otherwise forbidden second-order wave mixing,which is found to be enhanced by the quantum plasmon resonance too.This study reveals that the molecular-sized graphene could be used in the quantum regime for nanoscale nonlinear optical devices and ultrasensitive molecular sensors.

关 键 词：quantum plasmons nonlinear optical wave mixing graphene nanoflakes 

分 类 号：TQ127.11[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程]