University of Illinois at Urbana-Champaign · Department of Physics

Physics 498

The Physics of Strongly Correlated Systems

Academic Year 2000/2001

Fall Semester 2000

Instructor: Professor Eduardo Fradkin

Department of Physics
University of Illinois at Urbana-Champaign
Room 301B Loomis Laboratory, MC-704,
1110 W Green St, Urbana, IL 61801-3080
Phone: 217-333-4409
Fax: 217-333-9819
E-mail eduardo@buenosaires.physics.uiuc.edu
http://w3.physics.uiuc.edu/~efradkin/


The physics of Strongly Correlated Systems is a central area of research in Condensed Matter Physics. It is largely motivated by the problem of understanding High Temperature Superconductivity. However it has many conceptual connections with other problems in Condensed Matter such as the Quantum and Fractional Hall effects, Quantum Magnetism and Quantum Critical Behavior, the physics of quasi-one-dimensional conductors and quantum impurity systems. In this course I will discuss the main conceptual issues involved in the physics of Strongly Correlated Systems, as well as their connections with these other problems. This is an exciting area of research both in experiment and theory.

We have learned a lot in the past ten years. For instance, we now know that, unlike conventional superconductors, the high temperature superconductors have an order parameter with d-wave symmetry. Also new and unexpected phenomena has been discovered such as the existence of stripe phases. However, although many novel and interesting ideas have been proposed since the discovery of high temperature superconductivity, we still do not have a complete theoretical understanding of this phenomenon. In the past decade, however, we have gained a solid understanding of the physics of these problems, and many of these ideas have now become to coalesce into a coherent body of knowledge. The understanding of these problems has also required the development of new theoretical tools, which are not usually covered by the conventional graduate courses. The purspose of this class is to introduce the main ideas in the physics of Strongly Correlated Systems, to discuss what we understand of them, both in experiment and theory, and their implications for current and future research in the field. I will assume that the students have passed the Quantum Mechanics sequence (480-481) and the introductory Solid State Physics course (489). Although field theoretic methods are often used in this field, I will not assume that the student know quantum field theory (or many body physics which is the same). Rather I will develop the technique as we go along and at the level needed to understand the problem. The basic text for this class will be my book Field Theories of Condensed Matter Systems, published by Addison-Wesley in 1991, supplemented with additional material to cover topics not included there.

Below you will find a Syllabus for this class, Physics 498: The Physics of Strongly Correlated Systems. Here you will find links to the homework sets. You will be required to write a Term Paper. A list of proposed Term Papers will be posted here.

Term Paper

List of Suggested Term Papers: Please click here to see a list of suggested Term Papers.

Course Plan


The Hubbard Model as the prototype Strongly Correlatyed system. The Magnetic Instability in Fermi systems.

The unusual physics of one-dimensional Quantum Antiferromagnets. Quantum disordered states and Haldane gaps.

The Sigma Model picture of antiferromagnets in one and two dimensions. Quantum critical behavior. Bried review of the renormalization group.

Spin liquids, and other exotic beasts. Gauge theory approaches to Strongly Correlated Systems. When are these states physical?

Fermi liquids: when, where and why. Review of BCS theory of superconductivity.

Problems with the application of Fermi Liquid Theory to Strongly Correlated Systems. The abnormal ``normal state" of high Tc superconductors. Spin gaps and the underdoped cuprates. review of experimental status.

Non-Fermi liquids: Luttinger liquids in one-dimensional and quasi-one-dimensional systems: quantum wires, carbon nano-tubes and quantum Hall edges. Failure of (naive) extensions to higher dimensions. Stripe phases and electronic liquid crystal states. Luttinger physics and its connecions with the quantum Hall effect, and quantum impurity problems. Tunneling into non-Fermi liquids.

Bibliography: Please click here to see the bibliography.


Last updated 9/19/2000