Abstract
We present a concentrically corrugated near-field plate that can form a subwavelength near-field focal spot. The experimental plate consists of a coaxial aperture surrounded by nonperiodic concentric corrugations. The measured subwavelength patterns are shown to be significantly narrower than those created by a coaxial probe (without corrugations) of similar dimensions. Close agreement between simulated and measurement results is observed. Further, the subwavelength beam emitted by the corrugated near-field plate is shown to be narrower that of the coaxial probe, confirming the superior electromagnetic confinement achieved by the near-field plate over a focal length. Finally, the near-field plate is used to image two sources separated by subwavelength distances. The images obtained using the near-field plate exhibit significantly higher resolution than those obtained using a coaxial probe. The reported near-field plate will find use in near-field probing and microscopy applications.
Original language | English (US) |
---|---|
Article number | 5621935 |
Pages (from-to) | 3982-3988 |
Number of pages | 7 |
Journal | IEEE Transactions on Microwave Theory and Techniques |
Volume | 58 |
Issue number | 12 PART 2 |
DOIs | |
State | Published - Dec 2010 |
Externally published | Yes |
Keywords
- EM theory
- Electromagnetic (EM) probes
- metamaterial
- near-field imaging
- super resolution techniques
ASJC Scopus subject areas
- Radiation
- Condensed Matter Physics
- Electrical and Electronic Engineering