Tunable capturing and screening method for particles on graphene substrate by means of linear polarization planar optical wave

Abstract

The invention provides a tunable capturing and screening method for particles on a graphene substrate by means of linear polarization planar optical wave. The particles are arranged on the flat plate of the graphene substrate so that symmetric distribution of Poynting vectors around the particles is damaged, the total Poynting vectors on the particles are enabled not to be zero, and non-gradient optical force is generated; then the direction and the size of the total Poynting vectors on the particles are changed by changing the Fermi level of the flat plate of the graphene substrate so that the direction and the size of non-gradient optical force of the total Poynting vectors applying to the particles can be changed, and the movement tracks of the particles in an incident optical field can be regulated and controlled. The Fermi level of the flat plate of the graphene substrate can be changed by modes of changing an external electric field, temperature, injection light intensity and thickness of graphene so that the dielectric coefficient and electrical conductivity of graphene can be changed.

Description

technical field [0001] The invention relates to a method for tunable trapping and screening of particles above a graphene substrate by linearly polarized plane light waves, which can be applied to the fields of biology, medicine, nanometer manipulation and the like. Background technique [0002] Optical trapping and screening of tiny objects has always been a research hotspot in the field of optics. Optical gradient force plays an important role in various optical trapping technologies, such as optical tweezers and optical bundling through optical gradient force. However, optical gradient forces have the disadvantages of complex devices, non-tunable devices, and difficulty in trapping and screening nanometer-sized molecules. In 2008, Ward, T.J. et al proposed that the optical gradient force generated by circularly polarized light can capture and separate chiral molecules with nanometer size. However, the circularly polarized incident light still needs to be generated by co...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the complexity of the incident light source (that is, the incident light must be circularly polarized or elliptically polarized) and the limitation of the screening object (that is, the nanoscale molecule must have chiral structure), the gradient optical force generated by circularly polarized or elliptically polarized light is not tunable, and it is difficult to capture nano-sized achiral molecules, etc., and provide a system with simple system, convenient operation, ultra-sensitive, ultra-fast, The non-gradient optical force generated by linearly polarized plane light waves, which has the advantages of active tuning, captures and screens achiral nanometer-sized molecules above the graphene substrate plate, which can be used in the fields of biology, medicine, and nanomanipulation

Images