This award supports Professor Lu Sham and a junior associate of the University of California at San Diego to collaborate with Professor Friedhelm Bechstedt of the Friedrich Schiller University of Jena, Germany. They are studying coherence effects in strongly-correlated insulators and metals. In particular, they will investigate the possible detectability of coherence through the nonlinear optical response of the system. The collaborating research groups bring complementary expertise in many body theory and in optical properties of condensed matter systems. Strong electron-electron correlation plays a pivotal role in the electronic properties of modern metals and insulators such as the cuprate compounds and the heavy fermion compounds. If optically excited coherence effects can be shown to exist in theory, this will provide an operational definition for strong correlation in a large number of metals and insulators. In turn, this would lead to an optical means for experimentally observing strongly correlated behavior and an effective optical test for predictions of strong-correlation theories.
