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arXiv · 1401.7439

Charging of Heated Colloidal Particles Using the Electrolyte Seebeck Effect

Arghya Majee·Alois Würger
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Abstract

We propose a novel actuation mechanism for colloids, which is based on the Seebeck effect of the electrolyte solution: Laser heating of a nonionic particle accumulates in its vicinity a net charge Q, which is proportional to the excess temperature at the particle surface. The corresponding long-range thermoelectric field provides a tool for controlled interactions with nearby beads or with additional molecular solutes. An external field Eext drags the thermocharged particle at a velocity that depends on its size and absorption properties; the latter point could be particularly relevant for separating carbon nanotubes according to their electronic band structure.

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Arghya Majee, Alois Würger. 2014-01-29. Charging of Heated Colloidal Particles Using the Electrolyte Seebeck Effect. https://doi.org/10.1103/physrevlett.108.118301

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