Condensed Matter/Biophysics Seminar: Dr. Haidan Wen, Argonne National Laboratory  Add To Calendar

  • Date(s): Thursday, 11/16 2:00 PM to Thursday, 11/16 3:00 PM
  • Speaker: Dr. Haidan Wen
  • Host: Prof. Hyowon Park
  • Campus Address: SES 2214
Title: Ultrafast Dynamics of Electrons and their Interplay in Complex Oxides

Abstract: The quest of new states of matter in the time domain and the need for ultrafast control of material properties have been fueled by the recent advance of large-scale ultrafast x-ray facilities. These new experimental capabilities enable direct probe of structural dynamics with unprecedented spatial and temporal resolution, shedding light on the fundamental dynamical processes in materials. Combining ultrafast x-ray and optical probes, I will show how the electronic and structural dynamics intertwine in complex oxides and how these transient properties can be controlled on ultrafast time scales. In the first example, optical and terahertz excitations offer new pathways of controlling lattice structure and nanoscale thermal transport in ferroelectrics on ultrafast time scales. In the second example, an unconventional slowing down of charge ordering was observed in iron-based perovskites. Density function theory calculation shows that this non-thermal slowing down of electronic recovery can be traced to the magnetic interaction of the system. Looking into the future, the recent development of the multimodal, multiscale x-ray imaging platform will be discussed to go beyond ensemble average to probe localized dynamics.

Cm-Bio 11-16 Wen flyer