A method for measuring graphene carrier concentration using the Goos-Hanshin shift

Abstract

The invention discloses a method for measuring the carrier concentration of graphene by virtue of Goos-Hanchen shift. The variation of the Goos-Hanchen shift after introduction of the graphene is measured to measure the photoconductivity of the graphene and further measure the carrier concentration of the graphene. The method specifically comprises the following steps: covering a metamaterial with a refractive index approaching to zero with a single layer of graphene, obliquely emitting a terahertz beam to the surface of the graphene, detecting the Goos-Hanchen shift of reflected light, and calibrating the carrier concentration or the Fermi energy level of the graphene according to a relationship between the calibrated Goos-Hanchen shift and the carrier concentration or the Fermi energy level of the graphene. According to the method, a method of optically measuring the Goos-Hanchen shift without direct contact with a graphene sample is adopted, and is a non-contact and damage-free measurement method, so that additional influencing factors are avoided.

Description

technical field [0001] The method relates to a design for measuring the electrical properties of graphene by using an optical method, in particular to a method for measuring the carrier concentration of graphene by using terahertz Bogus-Hanchen shift. Background technique [0002] Graphene is a two-dimensional crystalline material in which carbon atoms are arranged in a honeycomb structure. Due to its excellent electrical, thermal and mechanical properties and its possible application potential, it has attracted attention in many fields. Graphene-based nanoelectronics Chemical devices have been well applied. Compared with traditional semiconductor materials, the carrier and Fermi energy of graphene have a larger adjustable space, which can be regulated by means of electricity, magnetism and chemical doping [Document 1, Geim A K, Novoselov K S. The rise of graphene [J]. Nature materials, 6(3):183-191(2007)]. [0003] To apply graphene to electrical devices, it is first nece...

AI Technical Summary

Problems solved by technology

[0006] This method aims to use optical means to solve the problem of graphene carrier concentration measurement. It discloses a method of loading graphene in the Goose-Hanchen displacement measurement system to realize the measurement of the Goose-Hanchen displacement change. The light guide of the corresponding graphene is obtained by the change of the Smith-Hanchen shift, and the design idea and implementation method of using the light guide to calibrate the graphene carrier concentration

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