Research On Surface Plasmon Polariton Opto-thermoelectric Optical Tweezers And Surface-enhanced Raman Scattering

Optical tweezers have made outstanding contributions in the microscopic field and are an important technical means to realize the capture and manipulation of micro-nano particles,which basic principle is the mechanical effect of momentum transfer between light and matter,Widely used in biology and medicine,chemistry,physics and other fields.Optical tweezers form a three-dimensional potential well in the light field that can capture micro-nano particles,which has the characteristics of no marking,non-contact,no damage,and real-time detection.Surface-enhanced Raman scattering(SERS)is a technique that utilizes the electromagnetic field localization and enhancement capabilities of metal nanostructures to achieve Raman signal enhancement,and the electromagnetic field strength is directly related to whether SERS technology can be realized.Compared with the traditional optical tweezers technology,based on the surface plasmon polariton focusing optical tweezer can form an electromagnetic field enhanced SPP virtual probe at the center of the optical axis,which can increase the Raman signal enhancement factor by two orders of magnitude;In addition,based on the surface plasmon polariton focusing optical tweezer can form a Gap structure between the metal particles and the gold film,resulting in ultra-high electromagnetic field strength.Under certain conditions,the Raman enhancement factor can reach more than 10~9.However,based on the surface plasmon polariton focusing optical tweezer still have the problem of the stability of metal particle capture.Due to the surface enhanced Raman spectroscopy technology,we need more stable particle capture.The Opto-thermoelectric nanotweezers appear in our field of vision with its efficient and stable particle capture efficiency characteristics.Combining two optical tweezers technology of surface plasmon polariton and Opto-thermoelectric nanotweezers,this paper proposes a surface plasmon polariton Opto-thermoelectric optical tweezers have achieved efficient and stable capture of micro-nano metal particles,and have very good SERS enhancement.The main contents of this paper include:1.According to the development history of optical tweezers technology,briefly introduced the research status and development prospects of surface plasmon optical tweezers and Opto-thermoelectric nanotweezers,and the basic principles of surface enhanced Raman spectroscopy,and propose surface plasmon polariton Opto-thermoelectric optical tweezers.2.The system introduces the technical principles of surface plasmon optical tweezers and Opto-thermoelectric nanotweezers,and does a theoretical analysis on the force of the particles.3.According to the effect of different metal film thickness,particle diameter,CTAC concentration and laser power on the surface plasmon polariton Opto-thermoelectric optical tweezers,the optical tweezers system was built.Experimental analysis and comparison of the influence of different influencing factors on the stability of surface plasmon Opto-thermoelectric optical tweezers in the capture of metal particles,and established the force model of metal particles in the optical tweezers system,analyze the capture stiffness of metal particles,to further optimize the surface plasmon polariton Opto-thermoelectric optical tweezers to do preliminary work.4.For the effect of surface plasmon polariton Opto-thermoelectric optical tweezers on the Surface-enhanced Raman scattering,create optical tweezers model on FDTD,the theoretical analysis of the enhancement of the local electromagnetic field of metal particles in optical tweezers is carried out.At the same time,the Raman??imaging experiment of the two-dimensional material MoS2 experimental sample in the optimized surface plasmon polariton Opto-thermoelectric optical tweezers,and achieved the desired effect,Lay the foundation for cell imaging technology for the next step.5.We summarized the work done and looked forward to its future development prospects.