Spectroscopic THz near-field microscope.
نویسندگان
چکیده
We demonstrate a scattering-type scanning near-field optical microscope (s-SNOM) with broadband THz illumination. A cantilevered W tip is used in tapping AFM mode. The direct scattering spectrum is obtained and optimized by asynchronous optical sampling (ASOPS), while near-field scattering is observed by using a space-domain delay stage and harmonic demodulation of the detector signal. True near-field interaction is determined from the approach behavior of the tip to Au samples. Scattering spectra of differently doped Si are presented.
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ورودعنوان ژورنال:
- Optics express
دوره 16 5 شماره
صفحات -
تاریخ انتشار 2008