Othmar Marti |
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Dr. sc. nat./ETH Zürich
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Other
Publications (258) View all
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Chapter: A Stand-Alone Scanning Near-Field Optical Microscope
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ABSTRACT: A scanning near-field optical microscope (SNOM), where the tip is scanned rather than the sample, is presented. The advantage of this ‘stand-alone’ type SNOM besides its compact setup is its ability to scan on arbitrarily extended samples. Furthermore, the sample can be manipulated during scanning (e.g. heated or extended), which may be of special interest in material sciences applications. An optical shear-force detection unit is implemented to control the tip-sample distance. Design problems specific to the stand-alone setup are discussed. Using uncoated fiber tips in reflection and transmission mode, lateral resolutions of better than 120 nm and 300 nm, respectively, are shown.02/2011: pages 139-144; -
SourceAvailable from: Othmar Marti
Chapter: Optical Near-Field Imaging by Force Detection
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ABSTRACT: A scanning force microscope (SFM) is used to detect near field light by a mechanism based on optical modulation of the image force between a semiconducting probe tip and a glass surface. The modulation stems from a phenomenon called surface photo-voltage (SPV). The performance of the mechanism for near-field microscopy is demonstrated by imaging a standing evanescent light wave and profiling structured samples. The lateral resolution is found to be better 110 nm (sub-wavelength) and a representative minimum detectable power is 0.1 pW/√Hz in air. A simple theoretical model is described which yields a good agreement with experimental results. As a first application of this technique imaging results on light induced space charge gratings in photorefractive materials are presented.02/2011: pages 109-122; -
SourceAvailable from: Othmar Marti
Article: New laser apparatus to measure oscillation amplitude down to picometer at megahertz frequencies.
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ABSTRACT: A laser setup to study shear oscillations at small amplitudes with resonance frequencies up to 3 MHz is presented. The new approach combines gauging of the Gaussian laser beam and a lock-in amplifier. The device is tested with a 3 MHz AT-cut quartz crystal. The oscillation amplitude at the edge of the electrode on the quartz crystal is measured with a resolution of 2 pm.The Review of scientific instruments 03/2010; 81(3):035116. · 1.52 Impact Factor -
SourceAvailable from: Othmar Marti
Article: High resolution vacuum scanning thermal microscopy of HfO and SiO
Applied Physics Letters 01/2008; 92:043122. · 3.84 Impact Factor -
Article: Atomic-Scale Resolution on the MgO(100) Surface by Scanning Force and Friction Microscopy
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ABSTRACT: MgO(100) surfaces have been imaged at atomic-scale resolution by scanning force and friction microscopy (SFFM). The single crystals of MgO were cleaved and studied in dry air using a small loading force (4 10−10 N). Topographic and friction images reveal a square lattice of protrusions with a measured spacing of 0.274 nm. This value is close to the 2D surface lattice parameter of the MgO(100) surface (0.299 nm). The largest corrugation observed in the topographic images is 0.04 nm. Large-scale images reveal nearly parallel cleavage steps, separated by an average distance of 150 nm and 0.4 nm high.EPL (Europhysics Letters) 07/2007; 26(9):659. · 2.17 Impact Factor