6533b870fe1ef96bd12cf006
RESEARCH PRODUCT
Sample–tip coupling efficiencies of the photon-scanning tunneling microscope
F. De FornelJ. P. GoudonnetL. Salomonsubject
Total internal reflectionMicroscopeMaterials sciencebusiness.industryScanning tunneling spectroscopyPhysics::OpticsAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materialslaw.inventionOpticslawLight beamComputer Vision and Pattern RecognitionExponential decayScanning tunneling microscopebusinessPenetration depthRefractive indexdescription
The photon-scanning tunneling microscope is the photon analog to the electron-scanning tunneling microscope. It uses the evanescent field due to the total internal reflection of a light beam in a prism, modulated by a sample attached to the prism. The exponential decay of the evanescent field is characterized by the penetration depth dp and depends on the angle of incidence θ, the wavelength, and the polarization of the incident beam. The 1/e decay lengths range from 150 to 265 nm as deduced from the expression of the electric-field intensity in the rarer medium for θ = π/2. If we place another optically transparent medium near the surface, frustrated total reflection occurs. It is shown theoretically and experimentally that, if we choose an appropriate angle of incidence θ(θ ≠ π/2) and change the index of refraction of one of the media, the decay length of the electric field can be extremely small, so that images with an improved resolution can be produced.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1991-12-01 | Journal of the Optical Society of America A |