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Quantifying electric field gradient fluctuations over polymers using ultrasensitive cantilevers.

ABSTRACT: An ultrasensitive cantilever, oscillating parallel to a surface in vacuum, is used to probe weak thermal electric field gradient fluctuations over thin polymer films. We measure the power spectrum of cantilever frequency fluctuations as a function of cantilever height and voltage over polymers of various compositions and thicknesses. The data are well described by a linear-response theory that calculates stochastic electric fields arising from thermally driven dielectric fluctuations.

SUBMITTER: Yazdanian SM

PROVIDER: S-EPMC2838734 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Quantifying electric field gradient fluctuations over polymers using ultrasensitive cantilevers.

Yazdanian Showkat M SM Hoepker Nikolas N Kuehn Seppe S Loring Roger F RF Marohn John A JA

Nano letters 20090601 6

An ultrasensitive cantilever, oscillating parallel to a surface in vacuum, is used to probe weak thermal electric field gradient fluctuations over thin polymer films. We measure the power spectrum of cantilever frequency fluctuations as a function of cantilever height and voltage over polymers of various compositions and thicknesses. The data are well described by a linear-response theory that calculates stochastic electric fields arising from thermally driven dielectric fluctuations. ...[more]

PMID: 19435337

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