CPM Seminar

Materials are said to involve "strongly correlated electrons" when their electronic properties cannot be explained in terms of the quasiparticle concept. High-temperature superconductors are the most notorious example of such materials. Theoretical attempts at understanding the properties of strongly correlated materials generally focus on simple models, such as the Hubbard model or the t-J model. After a general introduction, the basic Physics of the Hubbard model will be presented, with emphasis on its spectral properties, i.e., the energy distribution of individual electrons. Methods for calculating and measuring the so-called "spectral function" will be reviewed, and in particular a new theoretical method, the so-called "Cluster perturbation theory", will be briefly explained. As an application of this method, the "melting" of the Fermi surface in the Hubbard model will be illustrated.

Thursday, February 28th 2002, 16:00
Ernest Rutherford Physics Building, Keys Auditorium (room 112)