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Near-field reflection backscattering apertureless optical microscopy: application to spectroscopy experiments on
S Diziain1, J-L Bijeon, P-M Adam
1Institut Charles Delaunay, CNRS FRE 2848, Laboratoire de Nanotechnologie et d'Instrumentation Optique, Université de technologie de Troyes, 12 rue Marie Curie, BP 2060, 10010 Troyes cedex, France.
Ultramicroscopy
|June 1, 2006
Summary
This study presents an apertureless scanning near-field optical microscope (ASNOM) for spectroscopic analysis of opaque samples. It highlights the effectiveness of confocal microscopy and compares detection methods for enhanced near-field optical signal extraction.
Area of Science:
- Optics and Spectroscopy
- Microscopy Techniques
- Materials Science
Background:
- Apertureless scanning near-field optical microscopy (ASNOM) enables high-resolution optical analysis.
- Reflection backscattering configuration is suitable for opaque samples.
- Confocal microscopy offers depth-discrimination for signal isolation.
Purpose of the Study:
- To design and evaluate an ASNOM for spectroscopic experiments on opaque samples.
- To leverage confocal microscopy's depth-discrimination for near-field signal extraction.
- To compare lock-in and synchronous photon counting detection methods for spectroscopy.
Main Methods:
- Development of an apertureless scanning near-field optical microscope (ASNOM).
- Utilizing a reflection backscattering configuration.
- Employing confocal microscopy principles for depth discrimination.
- Systematic comparison of lock-in and synchronous photon counting detection.
Main Results:
- Successful spectroscopic experiments on latex beads using the designed ASNOM.
- Demonstration of efficient near-field optical signal extraction via depth discrimination.
- Comparative analysis of lock-in and synchronous photon counting methods in near-field spectroscopy.
Conclusions:
- The developed ASNOM is effective for reflection backscattering spectroscopy on opaque samples.
- Confocal depth discrimination enhances near-field signal extraction in ASNOM.
- Both lock-in and synchronous photon counting are viable detection methods, with specific advantages to be considered.
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