Giant plasmonic bubbles nucleation under different ambient pressures

TL;DR

This study investigates how ambient pressure affects the efficiency of plasmonic bubble nucleation around laser-irradiated gold nanoparticles in water, revealing a decrease in efficiency with higher pressures and providing a theoretical understanding.

Contribution

It provides a systematic experimental analysis of vaporization efficiency under different pressures and introduces a theoretical model to explain the thermal dynamics involved.

Findings

Efficiency of vapor bubble formation can reach up to 25%.

Vaporized water amount scales linearly with laser energy at low energies.

Efficiency decreases as ambient pressure increases.

Abstract

Water-immersed gold nanoparticles irradiated by a laser can trigger the nucleation of plasmonic bubbles after a delay time of a few microseconds [Wang et al., Proc. Natl. Acad. Sci. USA 122, 9253,(2018)]. Here we systematically investigated the light-vapor conversion efficiency, {\eta}, of these plasmonic bubbles as a function of the ambient pressure. The efficiency of the formation of these initial-phase and mainly water-vapor containing bubbles, which is defined as the ratio of the energy that is required to form the vapor bubbles and the total energy dumped in the gold nanoparticles before nucleation of the bubble by the laser, can be as high as 25%. The amount of vaporized water first scales linearly with the total laser energy dumped in the gold nanoparticles before nucleation, but for larger energies the amount of vaporized water levels off. The efficiency {\eta} decreases with increasing ambient pressure. The experimental observations can be quantitatively understood within a theoretical framework based on the thermal diffusion equation and the thermal dynamics of the phase transition.