Symmetry Principles in Strongly Correlated Systems

Stanford University, Stanford CA

Investigators

Abstract

This award supports research on theoretical condensed matter physics. The physics of strong electronic correlation remains one of the most active fields of research in condensed matter physics. These correlation effects often give rise to novel states of matter, such as superconductivity, magnetism and quantum Hall effect. Because these systems involve many strongly coupled degrees of freedom, traditional approaches based on perturbative expansions of a small parameter do not work. In this situation, symmetry principles and topological structures often prove to be extremely useful to organize the low-energy degrees of freedom and to extract non-perturbative information. Successful application of symmetry principles in condensed matter physics will not only help to solve the problems at had, but also deeply impact our understanding of the physical world at its most fundamental level. This research program contains three components: the SO(5) theory of high-temperature superconductivity, generalization of the quantum Hall effect to higher dimensions, and dissipationless spin currents in quantum spintronics. Motivations for these research topics originate from diverse sub-fields of physics, ranging from fundamental unity of laws of physics to practical applications in quantum semiconductor devices. Yet all of these seemingly different topics are tied together by a common mathematical thread and an unified physical principle. Successful execution of this diversified research program will not only invigorate our theoretical understanding of strongly correlated systems and enable practical applications of a new generation of quantum devices, but also educate a generation of students with broad interests and skill sets in all aspects of theoretical physics. %%% This award supports research on theoretical condensed matter physics. The physics of strong electronic correlation remains one of the most active fields of research in condensed matter physics. These correlation effects often give rise to novel states of matter, such as superconductivity, magnetism and quantum Hall effect. Because these systems involve many strongly coupled degrees of freedom, traditional approaches based on perturbative expansions of a small parameter do not work. In this situation, symmetry principles and topological structures often prove to be extremely useful to organize the low-energy degrees of freedom and to extract non-perturbative information. Successful application of symmetry principles in condensed matter physics will not only help to solve the problems at had, but also deeply impact our understanding of the physical world at its most fundamental level. This research program contains three components: the SO(5) theory of high-temperature superconductivity, generalization of the quantum Hall effect to higher dimensions, and dissipationless spin currents in quantum spintronics. Motivations for these research topics originate from diverse sub-fields of physics, ranging from fundamental unity of laws of physics to practical applications in quantum semiconductor devices. Yet all of these seemingly different topics are tied together by a common mathematical thread and an unified physical principle. Successful execution of this diversified research program will not only invigorate our theoretical understanding of strongly correlated systems and enable practical applications of a new generation of quantum devices, but also educate a generation of students with broad interests and skill sets in all aspects of theoretical physics. ***