CM-AMO Seminar | Quantum Criticality and Strongly Correlated Electrons, Speaker: Qimiao Si (Harry C. and Olga K. Wiess Professor of Physics and Astronomy, Rice University)

Speaker: Qimiao Si (Harry C. and Olga K. Wiess Professor of Physics and Astronomy, Rice University)

Electronic materials exhibit diverse properties, some of which "merely" inspire our curiosity while others change the way we live our lives. When electronic correlations are strong, the behavior is even richer but the theoretical description becomes notoriously difficult. The fundamental question is how the electrons are organized and, in particular, whether there are principles that are universal among the various classes of strongly correlated electron systems.

One such principle, which has come to prominence in recent years, is quantum criticality. A particularly lively setting arises in correlated systems at the border of antiferromagnetism. Here, theoretical studies have brought out new classes of quantum critical points, which are supported by mounting experimental results. In addition, there are growing indications that quantum criticality nucleates novel phases.

In this talk, I will introduce the basics about quantum criticality including the underlying motivations, and discuss some recent developments [1,2]. I will also consider some of the open issues and future directions, including the interplay among magnetic quantum criticality, electronic localization and unconventional superconductivity.

[1] Q. Si, arXiv:1012.5440, in "Understanding Quantum Phase Transitions", edited by L. D. Carr (2010). [2] Q. Si and F. Steglich, Science 329, 1161 (2010). Qimiao Si is the Harry C. and Olga K. Wiess Professor of Physics and Astronomy at Rice University.

More information about his background and research can be found at the following URL: http://faculty.rice.edu/report/FacultyDetail.cfm?DivID=1&DeptID=60&RiceID=705