Photoemission Electron Microscopy and Momentum Microscopy of 2D Transition Metal Chalcogenides

Sarah Harmer

Sarah Harmer, Flinders University

Photoemission is the most information rich and widely used techniques for the elucidation of the electronic structure, surface states and chemistry of materials. The NanoESCA III, recently commissioned in Flinders Microscopy and Microanalysis, is a photoemission electron microscope (PEEM) and angle resolved photoemission spectrometer (ARPES).

In PEEM mode it images surfaces by focusing and detecting electrons emitted from a material following irradiation with either UV or X-ray light. The primary capabilities include spatial mapping of the surface morphology, elemental and chemical composition, and the electron band-structure of materials.

Utilising both μ-ARPES and PEEM the resulting momentum microscopy allows insight into the electronic band-structure in 2D of high-performance materials, providing a fundamental understanding of how advanced materials and devices function. Coupled with density functional theory (DFT) calculations prediction and measurement of band structures and electronic properties of materials is realised.

About the presenter

Prof Sarah Harmer is an applied physicist who focuses on the spectroscopy analysis of transition metal chalcogenides from electronic structure to industrial minerals processing. She is the Founding of Director of Flinders Microscopy and Microanalysis (FMMA) which houses over $16M of National Infrastructure dedicated to the microanalysis of materials and biological systems, and Deputy Director of Flinders Institute for Nanoscale Science and Technology (FINST).

CI Harmer has over 20 years’ experience in the application of spectroscopic imaging of materials. She has developed a nanoreactor for Scanning Transmission X-ray Microscopy (STXM) to study the attachment of microbes to mineral surfaces in liquid under electrochemical control. More recently she has installed a NanoESCA III at FMMA as an open access user facility.