Tohari Mariam M, Lyras Andreas, AlSalhi Mohamad S
Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia.
Department of Physics, College of Science, King Khalid University, P.O. Box 9004, Abha 61421, Saudi Arabia.
Nanomaterials (Basel). 2018 Jul 12;8(7):521. doi: 10.3390/nano8070521.
Hybrid nanocomposites can provide a promising platform for integrated optics. Optical nonlinearity can significantly widen the range of applications of such structures. In the present paper, a theoretical investigation is carried out by solving the density matrix equations derived for a metal nanoparticles-graphene nanodisks-quantum dots hybrid system interacting with weak probe and strong control fields, in the steady state. We derive analytical expressions for linear and third-order nonlinear susceptibilities of the probe field. A giant self-Kerr nonlinear index of refraction is obtained in the optical region with relatively low light intensity. The optical absorption spectrum of the system demonstrates electromagnetically induced transparency and amplification without population inversion in the linear optical response arising from the negative real part of the polarizabilities for the plasmonic components at the energy of the localized surface plasmon resonance of the graphene nanodisks induced by the probe field. We find that the self-Kerr nonlinear optical properties of the system can be controlled by the geometrical features of the system, the size of metal nanoparticles and the strength of the control field. The controllable self-Kerr nonlinearities of hybrid nanocomposites can be employed in many interesting applications of modern integrated optics devices allowing for high nonlinearity with relatively low light intensity.
混合纳米复合材料可为集成光学提供一个有前景的平台。光学非线性可显著拓宽此类结构的应用范围。在本文中，通过求解为金属纳米颗粒 - 石墨烯纳米盘 - 量子点混合系统推导的密度矩阵方程，在稳态下对其进行了理论研究，该系统与弱探测场和强控制场相互作用。我们推导了探测场的线性和三阶非线性极化率的解析表达式。在相对低光强的光学区域获得了巨大的自克尔非线性折射率。该系统的光吸收光谱在由探测场诱导的石墨烯纳米盘局域表面等离子体共振能量处，由于等离子体组件极化率的负实部而在线性光学响应中表现出电磁诱导透明和无粒子数反转放大。我们发现该系统的自克尔非线性光学性质可由系统的几何特征、金属纳米颗粒的尺寸以及控制场的强度来控制。混合纳米复合材料可控的自克尔非线性可应用于现代集成光学器件的许多有趣应用中，从而在相对低光强下实现高非线性。
