skip to main content

SciTech ConnectSciTech Connect

Title: Nanofocusing of mid-infrared electromagnetic waves on graphene monolayer

Nanofocusing of mid-infrared (MIR) electromagnetic waves on graphene monolayer with gradient chemical potential is investigated with numerical simulation. On an isolated freestanding monolayer graphene sheet with spatially varied chemical potential, the focusing spot sizes of frequencies between 44 THz and 56 THz can reach around 1.6 nm and the intensity enhancement factors are between 2178 and 654. For 56 THz infrared, a group velocity as slow as 5×10{sup −5} times of the light speed in vacuum is obtained at the focusing point. When the graphene sheet is placed on top of an aluminum oxide substrate, the focusing spot size of 56 THz infrared reduces to 1.1 nm and the intensity enhancement factor is still as high as 220. This structure offers an approach for focusing light in the MIR regime beyond the diffraction limit without complicated device geometry engineering.
Authors:
 [1] ;  [2] ; ; ; ; ;  [1] ;  [3]
  1. College of Information Science and Engineering, National Huaqiao University, Xiamen 361021, Fujian (China)
  2. (China)
  3. Institute of Semiconductors, Chinese Academy of Science, 100083 Beijing (China)
Publication Date:
OSTI Identifier:
22280541
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; COMPUTERIZED SIMULATION; DIFFRACTION; GRAPHENE; INTERMEDIATE INFRARED RADIATION; POTENTIALS; SHEETS; SUBSTRATES; THZ RANGE; VISIBLE RADIATION