Precise measurement of static electricity between two approaching bodies achieved

Possible application to precise measurement techniques of faint, difficult to detect forces such as gravity

Jun 19, 2015

Researchers at the Graduate School of Engineering, Osaka University have developed a method for precisely measuring static electricity between two approaching bodies. Since this method can be applied as a new material evaluation technique, it will become important element technology for measuring powers that are too weak to detect such as the Casimir effect and universal gravity in the future.

Specially Appointed Lecturer Eiichi INAMI (currently Researcher, Research Center for Micro-nano Technology, Hosei University) and Visiting Associate Professor Yoshiaki SUGIMOTO


The classification of interaction forces between two approaching bodies is important in a wide range of research fields. Here, we propose a method to unambiguously extract the electrostatic force ( F ele ), which is one of the most significant forces. This method is based on the measurement of the energy dissipation under applied voltage pulse between an atomic force microscopy (AFM) tip and sample. It allowed us to obtain F ele as a function of the tip-sample distance and voltage including the distance-independent part, to which conventional AFM is insensitive. The obtained F ele curves nicely fit the analytical model, enabling estimation of the geometry of the tip. The distance-dependent contact potential difference could also be correctly obtained by the measured F ele , opening an alternative route to quantitative Kelvin probe force microscopy.

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To learn more about this research, please view the full research report entitled " Accurate Extraction of Electrostatic Force by a Voltage-Pulse Force Spectroscopy " at this page of the Physical Review Letters website.

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