Laser Pulse Heating of Spherical Metal Particles

TL;DR

This paper analyzes laser pulse heating of spherical metal particles across a wide size range, deriving analytical expressions for maximum temperature and identifying size-dependent temperature maxima.

Contribution

It introduces a comprehensive analytical approach using Mie solutions and heat transfer equations to predict temperature maxima for particles of various sizes under laser pulse heating.

Findings

Maximum temperature occurs at a specific finite particle size.

Derived analytical expressions match numerical simulations.

Temperature behavior depends on particle size and thermal properties.

Abstract

We consider a general problem of laser pulse heating of spherical metal particles with the sizes ranging from nanometers to millimeters. We employ the exact Mie solutions of the diffraction problem and solve heat-transfer equations to determine the maximum temperature at the particle surface as a function of optical and thermometric parameters of the problem. The main attention is paid to the case when the thermometric conductivity of the particle is much larger than that of the environment, as it is in the case of metal particles in fluids. We show that in this case at any given finite duration of the laser pulse the maximum temperature rise as a function of the particle size reaches an absolute maximum at a certain finite size of the particle, and we suggest simple approximate analytical expressions for this dependence which covers the entire range of variations of the problem parameters and agree well with direct numerical simulations.