The present work shows the oscillation of a microbubble using temperature gradients. This gradient is caused by the absorption of laser light by silver nanoparticles (AgNPs) immobilized on the tip of a single-mode optical fiber FO (9/125 μm). The immobilization of these nanoparticles was performed using the technique known as photodeposition. Subsequently, the tip with the nanoparticles was immersed in ethanol. We used a infrared (λ=1550 nm) laser with fiber optic output which was controlled (modulate) with a waveform generator. When the laser pulse is at its high level, a radial temperature gradient is generated and the liquid near the tip of the optical fiber evaporates creating a microbubble. This microbubble remains attached to the face of the optical fiber due to the Marangoni force (FM) that brings it to the point of highest temperature. When the laser pulse changes to its low level, the temperature gradient disappears and the Marangoni force becomes zero. This causes the buoyancy force (FB) to become predominant driving the microbubble to the surface. However, for a new laser pulse the cycle repeats itself, keeping the microbubble oscillating within a region. As the laser modulation frequency increases the oscillation distance of the microbubble decreases.
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