Development of an Ultrafast Low-Energy Electron Diffraction Setup

This book presents an Ultrafast Low-Energy Electron Diffraction (ULEED) system that reveals ultrafast structural changes on the atomic scale. The achievable temporal resolution in the low-energy regime is improved by several orders of magnitude and has enabled the melting of a highly-sensitive, molecularly thin layer of a polymer crystal to be resolved for the first time. This new experimental approach permits time-resolved structural investigations of systems that were previously partially or totally inaccessible, including surfaces, interfaces and atomically thin films. It will be of fundamental importance for understanding the properties of nanomaterials so as to tailor their properties.

Winner of the Jan Peter Toennies Physics Prize, awarded by the University of Göttingen, Germany Provides a detailed description of the working principle of ultrafast low-energy electron diffraction (ULEED) Presents crystalline monolayer polymer melting dynamics resolved for the first time Offers an easy-to-use extremely low-dose approach Includes supplementary material: sn.pub/extras

Autorentext
After studying ultrafast phase-change materials at the University of Technology in Sydney as well as the University of California Santa Barbara, Max Gulde returned to Germany. At the University of Göttingen, he received his diploma in physics in 2010 for the investigation of laser-triggered nano-emitters as potential sources for electron imaging and diffraction experiments. During this time, the idea of an ultrafast low-energy diffraction apparatus was born, ultimately leading to the development of ULEED. Today, Max Gulde uses ULEED together with molecular dynamics simulations to obtain insight into the non-equilibrium dynamics of molecularly thin, crystalline soft matter films.

Inhalt
Introduction.- Methods and Concepts.- Aspects of Ultrafast LEED.- Numerical Analysis of a Tip-Based Ultrafast Electron Gun.- Experimental Analysis of a Tip-Based Ultrafast Electron Gun.- Ultrafast PMMA Superstructure Dynamics on Free-Standing Graphene.- Conclusions.