Ultrafast spatiotemporal dynamics of a charge-density wave using femtosecond dark-field momentum microscopy

Abstract

Understanding phase competition and phase separation in quantum materials requires access to the spatiotemporal dynamics of electronic ordering phenomena on a micro- to nanometer length- and femtosecond timescale. While time- and angle-resolved photoemission (trARPES) experiments provide sensitivity to the femtosecond dynamics of electronic ordering, they typically lack the required spatial resolution. Here, we demonstrate ultrafast dark-field photoemission microscopy (PEEM) using a momentum microscope, providing access to ultrafast electronic order on the microscale. We investigate the prototypical charge-density wave (CDW) compound TbTe3 in the vicinity of a buried crystal defect, demonstrating real- and reciprocal-space configurations combined with a pump-probe approach. We find CDW order to be suppressed in the region covered by the crystal defect, most likely due to locally imposed strain. Comparing the ultrafast dynamics in different areas of the sample reveals a substantially smaller response to optical excitation and faster relaxation of excited carriers in the defect area, which we attribute to enhanced particle-hole scattering and defect-induced relaxation channels.

arXiv comment8 pages, 4 figures

References in corpus (5)

• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• Inhomogeneity of charge density wave order and quenched disorder in a high Tc superconductor
• Tracking Cooper Pairs in a Cuprate Superconductor by Ultrafast Angle-Resolved Photoemission
• Fermi surface nesting and charge-density wave formation in rare-earth tritellurides
• Ultrafast X-ray imaging of the light-induced phase transition in VO2