Event Time: Wednesday, March 3, 2021 | 11:00 am - 12:00 pm
Event Location:
Zoom
Add to Calendar 2021-03-03T11:00:00 2021-03-03T12:00:00 Special Seminar by Hans Boschker - Laser-Light for Epitaxy Event Information: https://ubc.zoom.us/j/68506225698?pwd=S2ZBRGsrbzZBQVVZZFNwYk5ZSEduQT09 Meeting ID: 685 0622 5698Passcode: 113399 Talk title: Laser-Light for EpitaxySpeaker: Hans Boschker, Max-Planck-Institute for Solid State Physics Stuttgart, Germany Abstract: Complex-oxide heterostructures are a leading example of quantum-matter heterostructures that open a new arena of solid-state physics. For the scientific development of this field and for a range of potential applications, the growth of high-purity heterostructures is required. We have developed a new thin-film deposition technique that is especially suited to the growth of oxide heterostructures with atomic precision. Thermal laser epitaxy (TLE) uses chemical elements as sources which are evaporated with continuous-wave lasers [1]. The lasers’ virtually arbitrary power density allows for the evaporation of almost all elements of the periodic table in the same setup. This is demonstrated by showing elemental metal films of a large range of elements; from high-vapour-pressure elements like S and Bi to low-vapour-pressure elements like W and Ta. I will discuss the benefits of thermal laser epitaxy for high-purity deposition of complex-oxide materials and heterostructures with almost all elements from the periodic table. Compared to existing methods such as molecular beam epitaxy and pulsed laser deposition, TLE is clean, simple, fast and versatile. TLE will open new possibilities for research and applications because it will enable higher quality heterostructures and it will expand the range of materials used in high-quality heterostructures. Furthermore, I will present results of a new substrate heater that is based on a ~10 µm laser [2]. This laser light is directly absorbed by oxide crystals and therefore allows for a heating system that is ultra-clean, has very fast ramp rates and can reach extremely high temperatures. [1] Film Deposition by Thermal Laser Evaporation, W. Braun and J. Mannhart, AIP Advances 9, 085310 (2019). [2] In situ Thermal Preparation of Oxide Surfaces, W. Braun, et al., Appl. Phys. Lett. Mater. 8, 071112 (2020). Short Bio: Hans Boschker studied applied physics at the University of Twente. He graduated in 2006, working on superconducting electronic devices under the supervision of Prof. Hilgenkamp. For his PhD thesis, he worked on the conducting LaAlO3/SrTiO3 interface, La0.67Sr0.33MnO3 thin films, La0.67Sr0.33MnO3 magnetocrystalline anisotropy and La0.67Sr0.33MnO3/SrTiO3 interfaces under the supervision of Prof. Rijnders and Prof. Blank at the University of Twente. He graduated Cum Laude in 2011. From 2011 to 2019, he worked as a scientist at the Max Planck Institute for Solid State Research in Stuttgart in the group of Prof. Mannhart, focusing on oxide device physics. Research highlights are the observation and study of the superconducting gap of the LaAlO3/SrTiO3 interface, the development of integrated circuits and nanoscale transistors using the LaAlO3/SrTiO3 interface, and the discovery of a conducting and magnetic electron system in atomically thin SrRuO3. He presently works at the Max Planck Institute for Solid State Research as a project manager on the development of thermal laser epitaxy. Event Location: Zoom
Event Time: Thursday, March 4, 2021 | 10:00 am - 11:00 am
Event Location:
Zoom
Add to Calendar 2021-03-04T10:00:00 2021-03-04T11:00:00 CM Seminar - Understanding strong correlation effects in materials: from HTSCs to ruthenates. Event Information: https://ubc.zoom.us/j/64183011430?pwd=U2lFNXEwSmlBRWVBdTR5OG1ZdlVSZz09 Meeting ID: 641 8301 1430 Passcode: 113399 Talk title: Understanding strong correlation effects in materials: from HTSCs to ruthenates.Speaker: Eva Pavarini - Institute for Advanced Simulation, Forschungszentrum Jülich Abstract: In the last decades, key theoretical advances and the increasing power of massively parallel supercomputers gave us access to the systematic study of strongly correlated materials, both at the single and two-particle level. In this talk I will present recent results for paradigmatic systems, high-temperature superconducting cuprates and layered ruthenates. For cuprates I will discuss spin-spin correlations and trends in the hopping integral range, t'/t; for ruthenates, the nature of the metal-insulator transition, Higgs bosons and the stability of xy-orbital ordering in the presence of sizable spin-orbit coupling [1-5]. [1] J. Musshoff, A. Kiani, and E. Pavarini, Phys. Rev. B 103, 075136 (2021) [2] J. Musshoff, G. Zhang, E. Koch, E.Pavarini, Phys. Rev. B 100, 045116 (2019) [3] G. Zhang, E. Gorelov, E. Sarvestani, and E. Pavarini, Phys. Rev. Lett. 116, 106402 (2016) [4] G. Zhang and E. Pavarini, Phys. Rev. B 95, 075145 (2017) [5] G. Zhang and E. Pavarini, Phys. Rev. B 101, 205128 (2020)   Event Location: Zoom