Neutron and X-Ray Scattering Study of Complex Oxides

Stanford University, Stanford CA

Investigators

Abstract

Complex oxides such as the high-Tc superconductors provide myriad possibilities to discover and study novel fundamental structural, magnetic and electronic phenomena and phases, and it is likely that only a small fraction of their scientific and technological potential has been realized so far. Neutron and x-ray scattering experiments play an invaluable role in this endeavor, as they yield essential structural and magnetic information about new phases of matter and the transitions between them. This individual investigator award supports a project involving crystal growth and scattering studies, as well as collaborations with experts using complementary experimental probes (such as photoemission, STM, optical spectroscopy, muSR and EXAFS), to address such timely questions as the nature of the electron-hole asymmetry in high-Tc superconductors and the role of disorder, phonons and coexisting or competing phases in these materials. The research is enabled by recent breakthroughs in the crystal growth of several pivotal materials, including the scantly-studied mercury-based compound Hg1201, the single Cu-O layer material with the highest value of Tc. Quantitative experiments on these materials are expected to become invaluable benchmarks for tests of theories. The extensive collaborations, enabled by the samples grown by the PI's undergraduate and graduate students, are anticipated to have a broad impact on the field. The PI's research at state-of-the-art x-ray and neutron facilities will offer valuable educational opportunities to train the next generation of materials physicists. Complex oxide materials such as the high transition temperature (high-Tc) superconductors provide myriad possibilities to discover and study novel fundamental structural, magnetic and electronic phenomena and phases, and it is likely that only a small fraction of their scientific and technological potential has been realized so far. Neutron and x-ray scattering experiments play an invaluable role in this endeavor, as they yield essential structural and magnetic information about new phases of matter and the transitions between them. Through crystal growth and scattering studies, as well as collaborations with experts using complementary experimental probes, this comprehensive project addresses unanswered questions relating to the superconductivity in the high-Tc superconductors. The research is enabled by recent breakthroughs in the crystal growth of several pivotal materials, including those with the highest values of Tc. Quantitative measurements are expected to become invaluable benchmarks for tests of theories. The extensive collaborations, enabled by the samples grown by undergraduate and graduate students, are anticipated to have a broad impact. Research at state-of-the-art x-ray and neutron facilities will offer valuable educational opportunities to train the next generation of materials physicists.