Emergent Quantum Phenomena in Layered Ruthenates and Iron Chalcogenides

****Technical Abstract****

Emergent quantum phenomena in correlated electron materials not only show promise for use in advanced applications in energy and information technologies, but also challenge current knowledge in condensed matter physics. This project will focus on two correlated material systems, i.e. layered ruthenates and iron chalcogenides. Both material systems provide remarkable opportunities for observing novel quantum phenomena due to complex interplay between the charge, spin, lattice and orbital degrees of freedom. For ruthenates, the project aims at searching for a novel quantum phase related to the quantum Griffiths phenomena and elucidating the mechanism for various unusual magnetic phase transitions. For iron chalcogenides, the goal is to seek emergent magnetic phenomena and unconventional superconductivity. This project will bring together a wide range of expertise including crystal growth, property characterization, neutron scattering and optical spectroscopy to enable comprehensive understanding of emergent quantum phenomena of correlated electrons. This project will be integrated with education activities through the following efforts: a) involving graduate and undergraduate students in the research, b) developing senior design projects for students majoring in Engineering Physics, and c) guiding students from a local high school in an independent research project.

****Non-Technical Abstract****

Materials with strong electron-electron correlation are commonly believed to hold the key for developing the next generation of electronics. The objective of this project is to search for novel quantum phenomena and investigate their underlying physics in two correlated material systems, i.e. layered ruthenates and iron chalcogenides. Both material systems have been found to show various exciting properties, such as metal-insulator transitions and unconventional forms of superconductivity and magnetic ordering. One of the remarkable characteristics of these materials is that their properties are sensitive to external stimuli and their properties can be tuned by magnetic field, pressure and chemical substitution; this provides wonderful opportunities to study the novel physics associated with complex phase transitions of correlated electrons. This project will bring together a wide range of expertise to enable comprehensive understanding of emergent quantum phenomena of correlated electrons. This project will be integrated with education activities through the following efforts: a) involving graduate and undergraduate students in the research, b) developing senior design projects for students majoring in Engineering Physics, and c) guiding students from a local high school in an independent research project.