Jainendra Jain

Pennsylvania State University

*The role of analogy in unraveling the fractional quantum Hall effect mystery*

Electrons confined to two dimensions produce, when exposed toa strong magnetic field, some of the most elegant emergent structures found in a many particle sytem,the fractional quantum Hall effect being a dramatic manifestation thereof. The quantum mechanical phases enter into the physics of this quantum fluid through a binding of an even number of quantized vortices to each electron, creating a new class of fermionic particles called composite fermions. The talk will mention the experimental clues and the physical logic that led us to composite fermions, and then describe how they provide a simple and unified explanation of various experimental facts, and motivate a unique microscopic theory that is practically exact. In particular, careful and detailed experimentation and theoretical studies have established that the fractional quantum Hall effect of electrons is an integral quantum Hall effect for composite fermions. Many recent developments and open issues will be discussed.