Optical Modulation Of Low-dimensional Semiconductors In Optical Micro-nano Structures

Optical modulator is the core component of optical communication,optical switching,optical integrated circuits,and other systems.The main function of optical modulator is to modify the optical signal as required.With the rapid development of the optoelectronic industry,higher modulation rate,lower energy consumption,miniaturization and integration of high-performance optical modulators have attracted a broad range of attention.Low-dimensional semiconductor materials,including two-dimensional materials,have improved new platforms for realizing high-performance and miniaturized micro-nano light modulators due to their excellent physical properties and extremely small size.As a result,a large number of micro-nano structured optical modulation devices have been proposed,such as two-dimensional material electro-optical modulators and zero-dimensional adjustable light transmitter.In this paper,light modulation based on low-dimensional semiconductor materials and optical micro-nano structures is investigated from both light absorption and light emission aspects.Firstly,a broadband and highly sensitive electro-optical modulator based on two-dimensional material graphene superlubricated characteristic nanoelectromechanical system is investigated.The modulation characteristics of this absorbing graphene electro-optic modulator are investigated under the influence of different voltages,graphene layers,binding energy coefficients and friction coefficients,and incident light polarization.Calculations show that the modulator can achieve a modulation bandwidth of 0.37-1.87?m,a modulation response as fast as 1ns,and a modulation voltage of 200 m V.Compared with conventional electro-optical modulators,this modulator has 2-3 orders of magnitude higher modulation bandwidth,approximately 3 orders of magnitude lower energy consumption,and the response speed is nearly 4 orders of magnitude faster than ordinary mechanical modulation.In addition,the modulator is more insensitive to the polarization angle of the incident light.When the angle of the incident light is less than 30°,full polarization modulation of the light can be achieved.The power consumption of this graphene superlubricated nanoelectromechanical system optical device is expected to overcome the thermodynamic limit of conventional optoelectronic devices.The modulator has important prospects for future applications in optoelectronic devices and optical communications.In addition,based on the principle of spontaneous radiation enhancement of dipoles and the principle of optical modulation of phase change materials with different crystallinity,the finite time domain difference method is used to study the micro-nano structures that can realize the active tunability of optical radiation of quantum light.Studies have shown that the structure can achieve a 282 times radiation enhancement of the magnetic dipole light source in the near-infrared band,and the quantum efficiency is maintained at>80%in a wide range.Then the passive regulation of spontaneous radiation enhancement of GST(Ge₂Sb₂Te₅)devices is realized and optimized by designing and changing the shape and size of GST material devices.The special optical properties of GST material are used to realize the device luminescence modulation under different crystallinity,and theoretically realize the active modulation of 60-280 times radiation enhancement with modulation depth up to 95%of quantum efficiency.This is an important guide to the active tuning of phase change materials in optical nanodevices for applications in spontaneous radiation from quantum light sources.Under the background of the rapid development of 5G communications,supercomputers,quantum communications,and big data industries,the absorption-type electro-optical modulation devices and actively tunable optical emitter devices we have studied are of great importance to the future development of various optoelectronic industries.