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arXiv · 1601.06054

Trapping of Single Nano-Objects in Dynamic Temperature Fields

Marco Braun·Alois Würger·Frank Cichos
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Abstract

In this article we explore the dynamics of a Brownian particle in a feedback-free dynamic thermophoretic trap. The trap contains a focused laser beam heating a circular gold structure locally and creating a repulsive thermal potential for a Brownian particle. In order to confine a particle the heating beam is steered along the circumference of the gold structure leading to a non-trivial motion of the particle. We theoretically find a stability condition by switching to a rotating frame, where the laser beam is at rest. Particle trajectories and stable points are calculated as a function of the laser rotations frequency and are experimentally confirmed. Additionally, the effect of Brownian motion is considered. The present study complements the dynamic thermophoretic trapping with a theoretical basis and will enhance the applicability in micro- and nanofluidic devices.

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Marco Braun, Alois Würger, Frank Cichos. 2016-01-22. Trapping of Single Nano-Objects in Dynamic Temperature Fields. https://doi.org/10.1039/c4cp01560f

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