Zhou Renlong, Yang Sa, Zhao Yongming
School of Physics and Information Engineering, Guangdong University of Education, No. 351 Xinggang Road, Guangzhou 510303, China.
Nanomaterials (Basel). 2022 Jan 27;12(3):416. doi: 10.3390/nano12030416.
We investigate a framework of local field, quality factor and lifetime for tunable graphene nanoribbon plasmonic-photonic absorbers and study the second order and third order nonlinear optical response of surface plasmons. The energy exchange of plasmonic-photonic absorber occurs in two main ways: one way is the decay process of intrinsic loss for each resonant mode and another is the decay process of energy loss between graphene surface plasmon (GSP) mode and the external light field. The quality factor and lifetime of the plasmonic-photonic absorber can be obtained with using the coupled mode theory (CMT) and finite difference time domain (FDTD) method, which are effectively tunable with changing Fermi energy, carrier mobility and superstrate refractive index. The evolutions of total energy and lifetime of GSP are also shown, which are helpful for the study of micro processes in a two-dimensional material plasmonic-photonic absorber. The strongly localized fundamental field induces a desired increase of second harmonic (SH) wave and third harmonic (TH) wave. The manipulation of the quality factor and lifetime of the GSP makes graphene an excellent platform for tunable two-dimensional material plasmonic-photonic devices to realize the active control of the photoelectric/photothermal energy conversion process and higher harmonic generation.
我们研究了用于可调谐石墨烯纳米带等离子体光子吸收器的局部场、品质因数和寿命框架，并研究了表面等离子体的二阶和三阶非线性光学响应。等离子体光子吸收器的能量交换主要通过两种方式发生：一种方式是每个共振模式的固有损耗的衰减过程，另一种是石墨烯表面等离子体（GSP）模式与外部光场之间的能量损耗的衰减过程。利用耦合模理论（CMT）和时域有限差分（FDTD）方法可以得到等离子体光子吸收器的品质因数和寿命，通过改变费米能量、载流子迁移率和覆盖层折射率可以有效地对其进行调谐。还展示了GSP的总能量和寿命的演变，这有助于研究二维材料等离子体光子吸收器中的微观过程。强局域基波场导致二次谐波（SH）波和三次谐波（TH）波的期望增加。对GSP的品质因数和寿命的操控使石墨烯成为用于可调谐二维材料等离子体光子器件的优异平台，以实现对光电/光热能量转换过程和高次谐波产生的主动控制。
