| Autor: |
Fehrenbacher, M., Winnerl, S., Döring, J., Kehr, S. C., Eng, L. M., Huo, Y. H., Schmidt, O. G., Yao, K., Liu, Y., Helm, M., Schneider, H. |
| Jazyk: |
angličtina |
| Rok vydání: |
2016 |
| Předmět: |
|
| Zdroj: |
Quantum Structured Infrared Photodetector International Conference (QSIP 2016), 12.-17.06.2016, Tel Aviv, Israel |
| Popis: |
We report a semiconductor-based superlens for sub-diffraction-limited near-field imaging at mid-infrared wavelengths. The superlens is based on a sequence of intrinsic and doped GaAs layers. Resonant enhancement of evanescent waves is accomplished here by exploiting the Drude response of a highly doped n-GaAs layer. Operation as a near-field superlens is validated by utilizing an aperture-less scattering near-field optical microscope (s-SNOM), which allows us to probe the image plane of the superlens with sub-wavelength resolution. In our experiments, gold stripes underneath the GaAs superlens are imaged by the s-SNOM. The s-SNOM comprises an atomic-force microscope (AFM), the tip of which is illuminated by mid-infrared radiation from a free-electron laser (FEL). Imaging results reveal sub-wavelength resolution better than λ/6 at the resonant wavelength of λ = 22.0 µm. In excellent accordance with the Drude-Lorentz model, the resonant wavelength for superlensing can easily be adjusted by changing the doping concentration. Our approach thus reveals a simple and versatile superlens implementation for infrared nanospectroscopy. Detector issues specific for s-SNOM will also be addressed. [1] M. Fehrenbacher, S. Winnerl, H. Schneider, J. Döring, S. C. Kehr, L. M. Eng, Y. Huo, O. G. Schmidt, K. Yao, Y. Liu, M. Helm, Nano Lett. 15, 1057 (2015) |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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