Abstract-Enhancement Effects of the Terahertz Near-Field Microscopy

Jian Huang 1,†

, Zhongbo Yang 1,†

, Dongshan Wei 1,* , Chunlei Du 1

 and Hong-Liang Cui 1,2,* 

1 Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China2 College of Instrumentation Science and Electrical Engineering, Jilin University, Changchun 130061, China† These authors contributed equally to this work

http://www.mdpi.com/2076-3417/5/4/1745

Terahertz near-field detection based and imaging on a nanotip has drawn wide attention following extensive applications of terahertz imaging technologies. Through the local enhanced electric field created by a terahertz nanotip in the near field, it is very likely to attain superior detection sensitivity and higher spatial resolution. This paper simulates the local enhancement effects of the terahertz near-field microscopy using a two-dimension finite difference time domain (2D-FDTD) method. Factors that influence the enhancement effects are investigated and analyzed in detail. Simulation results show that the size of the nanotip apex, the apex-substrate distance, dielectric properties of the substrate and the detected sample, etc., have significant impacts on the electric field enhancement and spatial resolution of the terahertz near-field nanotip, which can be explained from the effective polarizability of the nanotip-sample/substrate system.