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Updated: Aug 6, 2026
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Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment
Published on: April 4, 2017
Nonradiative surface plasmon assisted microscale Marangoni forces
Summary
Surface energy gradients drive liquid droplet motion when heated unevenly. This study demonstrates optical control of droplet movement via surface plasmon decay, enabling new microfluidic applications.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Temperature gradients on liquid droplet surfaces create surface energy gradients.
- These gradients can induce thermocapillary flow, leading to droplet motion.
- Optical excitation of surface plasmons can generate localized heating.
Purpose of the Study:
- To investigate droplet transport induced by surface plasmon decay.
- To demonstrate Marangoni forces as the driving mechanism for this motion.
- To explore applications in all-optical modulation and microfluidics.
Main Methods:
- Experimental observation of pico-liter droplet movement on a gold foil.
- Theoretical analysis using Marangoni effect principles.
- Computational fluid dynamics (CFD) visualization of droplet flow.
Main Results:
- Surface plasmon decay creates thermal gradients that drive thermocapillary flow.
- Marangoni forces were confirmed as the primary mechanism for droplet motion.
- Experimental evidence of surface modification due to plasmon excitation was observed.
Conclusions:
- Surface plasmon-induced thermocapillary flow offers a novel method for droplet manipulation.
- This phenomenon has potential applications in all-optical light modulation.
- The findings are relevant for microfluidics, droplet actuation, and SPR sensing.
