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Understanding interferometry for micro-cantilever displacement detection.

ABSTRACT: Interferometric displacement detection in a cantilever-based non-contact atomic force microscope (NC-AFM) operated in ultra-high vacuum is demonstrated for the Michelson and Fabry-Pérot modes of operation. Each mode is addressed by appropriately adjusting the distance between the fiber end delivering and collecting light and a highly reflective micro-cantilever, both together forming the interferometric cavity. For a precise measurement of the cantilever displacement, the relative positioning of fiber and cantilever is of critical importance. We describe a systematic approach for accurate alignment as well as the implications of deficient fiber-cantilever configurations. In the Fabry-Pérot regime, the displacement noise spectral density strongly decreases with decreasing distance between the fiber-end and the cantilever, yielding a noise floor of 24 fm/Hz(0.5) under optimum conditions.

SUBMITTER: von Schmidsfeld A

PROVIDER: S-EPMC4979913 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Understanding interferometry for micro-cantilever displacement detection.

von Schmidsfeld Alexander A Nörenberg Tobias T Temmen Matthias M Reichling Michael M

Beilstein journal of nanotechnology 20160610

Interferometric displacement detection in a cantilever-based non-contact atomic force microscope (NC-AFM) operated in ultra-high vacuum is demonstrated for the Michelson and Fabry-Pérot modes of operation. Each mode is addressed by appropriately adjusting the distance between the fiber end delivering and collecting light and a highly reflective micro-cantilever, both together forming the interferometric cavity. For a precise measurement of the cantilever displacement, the relative positioning of ...[more]

PMID: 27547601

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