RUI-TAILORING LOW-DIMENSIONAL QUANTUM MAGNETS TO EXPLORE PHASE DIAGRAMS AND CRITICAL POINTS

Eastern Washington University, Cheney WA

Investigators

Abstract

****NON-TECHNICAL ABSTRACT**** Quantum magnets constitute a major research area in chemistry, physics and materials science. The phase diagrams of such materials can be derived for a range of parameters, each of which tells us something about how electrons interact with each other and their environment. An ability to tune the parameter space is crucial to developing new materials of potential benefit to society. This project, funded by the Solid State and Materials Chemistry Program and the Condensed Matter Physics Program in the Division of Materials Research, targets the creation of architectures with varying spatial dimensionality (i.e., 1D, 2D, or 3D) to place targeted materials near these critical regions. Therein, strange things can happen to electrons; for example, theory predicts that superconductivity and other states of matter may emerge as a result of these peculiarities. To manipulate the magnetic properties of our materials, the researchers employ chemical means, high-pressure, and high magnetic fields. The highly collaborative project involves several national and international user facilities. This provides unique opportunities for undergraduate students to travel with the principal investigator to partake in many of the planned experiments as well as to attend professional conferences. Student involvement in every aspect of the project stimulates their growth and enthusiasm as young scientists as well as provide the impetus to begin graduate work in the future or to go on to careers in the chemical and physical sciences. Mentorship and training of undergraduate students is a high priority of this project. ****TECHNICAL ABSTRACT**** The solid state provides many examples of model quantum systems however, the role of disorder and the details of atomic-scale chemistry hinder our ability to control crucial parameters in any systematic way. This project, funded by the Solid State and Materials Chemistry Program and the Condensed Matter Physics Program in the Division of Materials Research, hypothesizes that the key to developing a tunable quantum simulator is to identify appropriate molecular systems. Indeed, metal-organic magnets are materials whose primary structural building blocks embody a quantum component (a transition metal ion with S = 1/2, 1 or 3/2 ground state) coupled through a flexible and highly tunable organic framework. Therefore, studies are carried out to tune these systems via chemical design so that (a) they form structures able to promote magnetic exchange in well-defined topologies; and (b) the single-ion anisotropy and strength of interactions between the chosen magnetic units is modified. Systematic exploration of phase diagrams by tuning real materials toward phase boundaries and quantum critical points (QCP) using chemical means, hydrostatic pressure, and high magnetic fields is at the core of this project. Undergraduate students, from all backgrounds, carry out the syntheses and assist with data analysis and characterization of samples, travel to state-of-the-art research facilities, and attend/present their work at professional conferences. Student involvement in every aspect of the project stimulates their growth and enthusiasm as young scientists as well as provide the impetus to begin graduate work in the future or to go on to careers in the chemical and physical sciences. Mentorship and training of undergraduates is a high priority of this project.