Maximilian Goldmann | Searcharxiv

arXiv2016

Nanofocusing, shadowing, and electron mean free path in the photoemission from aerosol droplets

Angle-resolved photoelectron spectroscopy of aerosol droplets is a promising method for the determination of electron mean free paths in liquids. It is particularly attractive for volatile liquids, such as water. Here we report the first angle-resolved photoelectron images of droplets with defined sizes, viz. of water, glycerol, and dioctyl phthalate droplets. Example simulations of water droplet photoelectron images and data for electron mean free paths for liquid water at low kinetic energy (< 3eV) are provided. We present an approach that allows one to gradually vary the conditions from shadowing to nanofocusing to optimize the information content contained in the photoelectron images.

physics.chem-ph↗

arXiv2015

Electron mean free path from angle-dependent photoelectron spectroscopy of aerosol particles

We propose angle-resolved photoelectron spectroscopy of aerosol particles as an alternative way to determine the electron mean free path of low energy electrons in solid and liquid materials. The mean free path is obtained from fits of simulated photoemission images to experimental ones over a broad range of different aerosol particle sizes. The principal advantage of the aerosol approach is twofold. Firstly, aerosol photoemission studies can be performed for many different materials, including liquids. Secondly, the size-dependent anisotropy of the photoelectrons can be exploited in addition to size-dependent changes in their kinetic energy. These finite size effects depend in different ways on the mean free path and thus provide more information on the mean free path than corresponding liquid jet, thin film, or bulk data. The present contribution is a proof of principle employing a simple model for the photoemission of electrons and preliminary experimental data for potassium chloride aerosol particles.

physics.chem-ph↗