Phase coexistence in Gallium nanoparticles controlled by electron excitation

TL;DR

This study demonstrates that electron excitation can reversibly control phase coexistence in Gallium nanoparticles, enabling rapid and energy-efficient manipulation of their structural states.

Contribution

It introduces a method to control phase coexistence in Gallium nanoparticles using low-energy electron excitation with high reversibility.

Findings

Reversible coexistence of gamma, beta, and liquid phases observed.

Only 1 pJ of energy per nanoparticle needed for phase control.

Phase transformations occur within less than a microsecond.

Abstract

In Gallium nanoparticles of 100 nm in diameter grown on the tip of an optical fiber from an atomic beam we observed equilibrium coexistence of gamma, beta and liquid structural phases that can be controlled by e-beam excitation in a highly reversible and reproducible fashion. With 2 keV electrons only 1 pJ of excitation energy per nanoparticle is needed to exercise control, with the equilibrium phase achieved in less than a few tenths of a microsecond. The transformations between coexisting phases are accompanied by a continuous change in the nanoparticle film's reflectivity.