Abstract
We investigate in detail the interferometric nature of the signal delivered by an apertureless scanning near-field optical microscope (SNOM). This nature is first brought to the fore by near-field images of an integrated waveguide. The detection process of an evanescent wave generated by total internal reflection is then studied by both lateral near-field scans and signal detection as a function of the tip-to-sample distance. This study permits interpretation of fringe patterns appearing in apertureless SNOM images and provides important information about the nature of the signal. In particular, both experimental data and simple calculations show that, because of interference with background light coming from the sample, the detected signal can describe the complex field amplitude, or the field intensity, or a subtle mix of both, depending on the tip environment and the tip position.
© 2003 Optical Society of America
Full Article | PDF ArticleMore Like This
Lewis Gomez, Renaud Bachelot, Alexandre Bouhelier, Gary P. Wiederrecht, Shih-hui Chang, Stephen K. Gray, Feng Hua, Seokwoo Jeon, John A. Rogers, Miguel E. Castro, Sylvain Blaize, Ilan Stefanon, Gilles Lerondel, and Pascal Royer
J. Opt. Soc. Am. B 23(5) 823-833 (2006)
C. H. Chuang and Y. L. Lo
Opt. Express 15(24) 15782-15796 (2007)
Chin-Ho Chuang and Yu-Lung Lo
Opt. Express 16(22) 17982-18003 (2008)