Enhanced light confinement in a near-field optical probe with a triangular aperture.
We present a probe concept for scanning near-field optical microscopy combining the excellent background suppression of aperture probes with the superior light confinement of apertureless probes. A triangular aperture at the tip of a tetrahedral waveguide (full taper angle approximately 90 degrees ) shows a strong field enhancement at only one rim when illuminated with light of suitable polarization. Compared to a circular aperture of equivalent size, the resolution capability is doubled without loss of brightness. For a approximately 60 nm sized triangular aperture, we measured an optical resolution <40 nm and a transmission of approximately 10(-4).
Naber
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A
Physics Institute, Wilhelm-Klemm-Strasse 10, D-48149 Münster, Germany. naber@uni-muenster.de
Molenda
D
D
Fischer
U C
UC
Maas
H-J
HJ
Höppener
C
C
Lu
N
N
Fuchs
H
H