Basic Information; Overview; Principle Of Operation - NT-MDT NTEGRA Spectra Instruction Manual

NTEGRA Spectra Probe NanoLaboratory. SNOM Measuring Head. Instruction Manual

1. Basic Information

1.1. Overview

SNOM measuring head serves for measurements with the scanning near-field optical
microscopy (SNOM) with the instrument NTEGRA Spectra PNL (configuration
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Upright) . This head is an optional part of the instrument.
SNOM functionality is enabled by aperture probes which operates both as microsized
apertures and as SPM cantilevers. Optical resolution of data is determined by diameter
(50÷150 nm) of an aperture.
SNOM technique provides study of surface optical properties (spatial distribution of
reflectivity and transmittivity over the sample surface, distribution of fluorescent
characteristics, etc.) of various objects with resolution several times higher the diffraction
limit. For high resolution, the probing radiation is focused on an aperture of size much
less than the radiation wavelength, passes through it as an evanescent electromagnetic
wave, and reaches the sample located in the near field vicinity of the aperture. The
operating aperture-sample distance is of order of several nanometers and so the light spot
on the sample is approximately of the size of the aperture. This eliminates diffraction
smearing of images taken with scanning the sample with the SNOM probe.

1.2. Principle of Operation

SNOM measuring head used with the NTEGRA Spectra PNL (Upright configuration)
operates in the optical scheme of the Transmission Illumination Mode, which is used for
transparent or semitransparent samples.
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For details on design and operation of the PNL, refer to manual NTEGRA Spectra Probe NanoLaboratory
(Upright Configuration with Renishaw Spectrometer)
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