The field of Condensed Matter Physics and Materials Science integrates the knowledge and tools of chemistry and physics with the principles of engineering to understand and optimize the behavior of materials, as well as to create new and improved materials to help fulfill the missions of the Department of Energy.
Condensed-Matter Physics & Materials Science Seminar
"Magnetometry Study of Underdoped Cuprate YBa2Cu3O6.55"
Presented by Fan Yu, University of Michigan
11 am, Bldg. 734, ISB. Conf. Rm. 168
Friday, April 28, 2017, 11:00 am
Hosted by: '''''''Qiang Li'''''''
This talk would be focused on my study of the phase diagram of underdoped cuprate YBa2Cu3O6.55 using torque magnetometry as well as my exploration of extending magnetometry method into even higher magnetic fields (>45T) using pulsed magnet. The complex phase diagrams of cuprates are sometimes referred to as "competing orders", where a large variety of ordering tendencies are known to (co-)exist. Our experiment managed to reveal an anomaly on the magnetic susceptibility, which we believe was related to charge density wave transition. Particularly interesting is that this anomaly is observed in the strong diamagnetic regime where vortex liquid exists. We believe this should be considered as a direct experimental evidence for the picture of "competing orders". To further our understanding of the quantum vortex liquid, experiments at mK temperatures and at magnetic field exceeding 40 Tesla are necessary. During my PhD study, considerable amount of time was devoted to developing a reliable magnetometry method utilizing the pulsed magnet at NHMFL, Los Alamos. I would like to present my trail-and-error as well as the proposition of "time-delayed probe design", which should be able to bypass the inherent noise of a pulsed environment.
Explores the electronic structure and electrodynamics of topological insulators and strongly correlated electron systems, with particular attention to emergent phenomena, such as superconductivity and magnetism, using angle-resolved photoemission (ARPES) and optical spectroscopy.
Studies the role of antiferromagnetism in high-temperature superconductors. The interaction of charge carriers with magnetic moments is of critical importance but remains a challenge to understand. .
Carries out basic studies of the structural, electronic and magnetic properties of condensed matter systems using synchrotron-based x-ray scattering techniques. .
Conducts basic research over a wide swath of theoretical physics, ranging from strongly correlated electrons to first principle electronic structure theory.
Studies both the microscopic and macroscopic properties of complex and nano-structured materials with a view to understanding and developing their application in different energy related technologies
Addresses key open questions in HTS physics such as the dimensionality of the HTS phenomenon, the spin and charge of free carriers, the nature of the superconducting transition, the role of charge stripes (if any) in the HTS state, the nature of the overdoped metallic state, and more.
Span a wide range of quantum matter systems, including superconductors, superfluids, supersolids, electronic liquid crystals, topological insulators superconductors & superfluids, heavy fermions, and spin liquids. Throughout, the focus is on development of innovative techniques and approaches to each problem.
Utilizes advanced electron microscopy techniques to study nanoscale structure and defects that determine the utility of functional materials, such as superconductors, multiferroics, and other energy related systems including thermoelectrics, photovoltaics, and batteries.
The Condensed Matter Physics and Materials Science Department is part of Brookhaven National Laboratory's Energy Sciences Directorate.