Abstract:
Serving a broad user community at BESSY II, our research addresses key areas of the High-Tech Agenda Germany including quantum technologies and technologies for climate-neutral mobility. Progress in materials design hinges on a profound understanding of the fundamental properties, notably electronic structure, of state-of-the-art use-case materials and well-defined model systems. This knowledge aids in theoretical development and the rational optimization of material functionalities.
PEAXIS is a specialized soft X-ray spectroscopy endstation that integrates resonant inelastic X-ray scattering (RIXS) and photoelectron spectroscopy (XPS) within a unified measurement platform [1, 2] dedicated to probe electronic excitations and quasiparticles based on spin, orbital and lattice degrees of freedom.
In this presentation, I would highlight recent scientific achievements enabled by PEAXIS. Since its inception, the instrument caters to a variety of users in the field of quantum and energy materials. Among others, investigations of d-d and charge transfer excitations and unique dispersive excitations in model quantum material systems were carried out. Furthermore, RIXS measurements were also used to probe distinct chemical states of oxygen products that contribute to the redox reaction inherent to next generation cathodes in rechargeable batteries. These studies demonstrate the versatility of PEAXIS in connecting spectroscopic signatures with the microscopic mechanisms that govern material functionality.
[1] Lieutenant, K., Hofmann, T., Schulz, C., Yablonskikh, M. V., Habicht, K., & Aziz, E. F. (2016). Design concept of the high-resolution end-station PEAXIS at BESSY II: Wide-Q-range RIXS and XPS measurements on solids, solutions, and interfaces. Journal of Electron Spectroscopy and Related Phenomena, 210. https://doi.org/10.1016/j.elspec.2015.08.009.
[2] Schulz, C., Lieutenant, K., Xiao, J., Hofmann, T., Wong, D., & Habicht, K. (2020). Characterization of the soft X-ray spectrometer PEAXIS at BESSY II. Journal of Synchrotron Radiation, 27(1), 238–249.https://doi.org/10.1107/S1600577519014887
Short Bio:
Dr. Deniz Wong is an instrument scientist at the Helmholtz-Zentrum Berlin (HZB) and is responsible for the PEAXIS endstation at BESSY II. He obtained his degree in Chemistry at National Taiwan University under the TIGP fellowship of Academia Sinica in 2013. During his early research career, he investigated a diverse range of functional and energy materials at the Advanced Materials Laboratory, working under the mentorship of Prof. Kuei-Hsien Chen and Prof. Li-Chyong Chen.
Today, his work at PEAXIS focuses on the development and application of soft X-ray resonant inelastic X-ray scattering (RIXS) to investigate the electronic structure and elementary excitations of quantum and energy materials. Through PEAXIS, he supports research aimed at uncovering the microscopic interactions between electrons, spins, orbitals, and lattice degrees of freedom that govern functional properties in advanced materials.