PAMS Seminar: "Watching Electrons Move at Interfaces: Visualizing Charge and Spin Dynamics Using Ultrafast XUV Spectroscopy" by Dr. Robert Baker

PAMS Seminar: "Watching Electrons Move at Interfaces: Visualizing Charge and Spin Dynamics Using Ultrafast XUV Spectroscopy" by Dr. Robert Baker
Date and time
4:00 PM - 5:00 PM, March 04, 2021
Description

Dr. Robert Baker
National eXtreme Ultrafast Science (NeXUS)
Ohio State University

Abstract:
Directly observing electron dynamics at surfaces is required to understand and control the material properties that determine efficiency of many applications including efficient energy conversion as well as ultrafast information processing.  Toward this goal, we have developed extreme ultraviolet reflection-absorption (XUV-RA) spectroscopy as a surface-specific analog of XUV transient absorption.  This method combines the benefits of traditional X-ray absorption spectroscopy, such as element, oxidation, and spin state resolution, with surface sensitivity and ultrafast time resolution.  Using this technique, we investigate charge and spin dynamics in materials with applications ranging from photocatalysis to optical control of magnetic switching.  In one example, we describe a systematic comparison of surface and bulk electron polaron formation in hematite showing that surface self-trapping dynamics differ significantly from bulk and that these dynamics can be systematically tuned by surface molecular functionalization offering the possibility for design of photocatalytic interfaces with enhanced carrier transport based on earth abundant materials.  In a second example, we highlight evolving applications of XUV-RA spectroscopy to study spin dynamics at surfaces.  Applications include understanding ultrafast spin crossover in magnetic semiconductors as well as control of spin polarized electron dynamics at chiral photochemical interfaces.  Last, I will describe capabilities that will soon become available at the NSF National eXtreme Ultrafast Science Facility (NeXUS) that is currently under development at Ohio State University.

This seminar will be held exclusively on Zoom (955 5209 1021). Please visit the Physics Seminars page for a link.

Event sponsor
Admission

Free

Open to public, alumni, current students, faculty, future students, staff
Location
Zoom: 955 2509 1021