Colloquium

The physics of frustration in quantum magnets

Young Lee   
MIT
Wednesday, September 13, 2006
Higgins 310, 4 pm

In this talk, I will discuss our quest for the "holy grail" of spin frustration. One of the central issues in condensed matter physics involves understanding the exotic phases which emerge from collections of interacting electrons. New states of matter may be produced if quantum effects and frustration conspire to prevent the ground state from achieving classical order. After discussing the history of this problem and the motivation for our work, I will describe our recent experimental progress. In particular, I will explain some new physics we have learned from neutron scattering measurements on a spin-frustrated material based on the two-dimensional Kagome lattice. Our observations reveal the presence of spin-textures related to chirality and the existence of an unusual spin-wave mode with zero velocity.