ELFT HÍRADÓ

[<vera.horvath AT eli-alps.hu>]

Előadó:             L. Robert Baker (The Ohio State University and NSF NeXUS)
Cím:                 Visualizing Electron Dynamics at Interfaces Using XUV
Light
Helyszín:             az ELI ALPS konferenciaterme (Szeged, Wolfgang Sandner
utca 3.)
Időpont:             2023. február 7., 14 óra

Az előadás rövid összefoglalója:

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.

A szeminárium angol nyelvű. Minden érdeklődőt szívesen látunk, de online is
követhető a következő linken:
https://teams.microsoft.com/l/meetup-join/19%3ameeting_ODJkM2MwNjAtOWM1NS00ZGEyLWJjODMtNmUzZTE2MzcxMWNi%40thread.v2/0?context=%7B%22Tid%22%3A%22b207389a-c5cb-4cb0-a1ad-227b94e96448%22%2C%22Oid%22%3A%22c993efcb-59ae-4652-9f68-d7a313727128%22%2C%22IsBroadcastMeeting%22%3Atrue%2C%22role%22%3A%22a%22%7D&btype=a&role=a

Horváth Vera