Study On Silicon-based Nanolaser Based On Surface Plasmon Polariton

With the large-scale development of integrated circuits,the degree of integration of transistors has become higher and higher.Chips with electrons as the carriers are affected by delay,power consumption,heat dissipation and other problems,which challenges Moore’s law.Introducing photons into chips to realize the interaction between photons and electrons is the best solution for high-speed information transmission and processing,especially for integrating microelectronic devices and photonic devices into silicon material platform.As an important part of optical interconnection system,silicon-based light source are often embedded in various optical modules by means of hybrid integration.The size of the laser is relatively large,making it difficult to achieve large-scale integration.Monolithic integrated light sources are considered to be the ultimate solution for on-chip light source.To overcome the size mismatch between microelectronic devices and photonic devices,realize silicon-based optoelectronic integration,it is particularly important to compress photonic devices to the nanometer level.In this paper,a new laser model is proposed,in which In Ga As/In P material is epitaxially grown in the V-shaped trench of the silicon substrate through the high aspect ratio restriction technology,and the surface plasmons are introduced by the deposition of dielectric layer and metal layer to achieve resonance in the nano-scale cavity,and finally amplification and excitation are obtained under stimulated radiation.Combining silicon materials with III-V materials with good light-emitting performance,silicon as a waveguide and III-V as an active area,combined with surface plasmons,theoretically a practical silicon-based light source can be realized.The COMSOL Multiphysics software is used to establish a simulation model to analyze the surface plasmon mode inside the device,and the physical mechanism of surface plasmons propagation between the metal layer and the dielectric layer ia also studied.Four gap height gradients of 4 nm,7 nm,14 nm,and 20 nm are selected,and the width of the metal ridge varies from 150 nm to 340 nm,the law of mode characteristic parameters,comprehensive performance parameters,resonant cavity quality parameters,and lasing threshold in the optical communication band has been discussed,and finally the specific device structure and model parameters are determined,which provides a certain theoretical basis for device preparation.The simulation results show that the structure has a good mode limiting capability,can realize deep sub-wavelength confinement of the output light field,and has small propagation loss.When the gap height is 4 nm and the metal ridge width is 230 nm,the optimal value of the comprehensive performance of the waveguide can be obtained and the threshold level remains low.At this time,the mode field area is0.00265,and the gain threshold is 1.15μm^-1.The above content provides a certain theoretical reference for the laser simulation.In the experimental part,we adopts hydrothermal method to grow zinc oxide nanowires on silicon substrates,through atomic layer deposition and magnetron sputtering technology to grow aluminum oxide dielectric layer and metal silver layer respectively,thus a simple Si-based nanolaser based on surface plasmon polariton has been prepared.SEM,XRD and micro-area PL spectroscopy are used to characterize the morphology of the luminescent material,physical property analysis and luminescence performance test.At the room temperature,the device is optically pumped by a 325 nm solid-state laser and the laser emission spectrum and spot of the device were successfully obtained by change the optical pump power gradiently.The whole study provides a theoretical basis and experimental scheme for the development of miniaturized silicon-based light source.