1.
Opt Express
; 17(26): 23785-92, 2009 Dec 21.
Article
in English
| MEDLINE
| ID: mdl-20052089
ABSTRACT
We have realized a differential Near-field Scanning Optical Microscope (NSOM) working with subwavelength resolution in the THz spectral region. The system employs a quantum cascade laser emitting at lambda approximately 105 microm as source, and the method, differently from conventional NSOM, involves diffracting apertures with size comparable to the wavelength. This concept ensures a higher signal-to-noise level at the expense of an additional computational step. In the implementation here reported lambda/10 resolution has been achieved; present limiting factors are investigated through finite difference time domain simulations.