Quantum Spin Hall Effect and Topological Insulators
December 08, 2008 – December 19, 2008
KITP in Santa Barbara, California
Kavli Institute for Theoretical Physics (KITP) in Santa Barbara, California
Coordinators: Leon Balents, Charles Kane, Laurens Molenkamp, Shoucheng Zhang
Search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These topological insulators have a bulk insulating gap, but have topologically protected edge states due to time-reversal symmetry. In two dimensions, the edge states give rise to the quantum spin Hall (QSH) effect, where states with opposite spins counter-propagate at a given edge in the absence of any external magnetic field. Some basic signatures of the QSH effect has been observed experimentally in HgTe quantum wells. In three dimensions, the surface states of topological insulators contain an odd number of Dirac points, which can be observed in photo-emission experiments.
The objective of this workshop is to bring theorists and experimentalists together to discuss exciting topics in this rapidly developing field, including the search for new materials which display the QSH effect, possibly at room temperature; direct physical measurements of the topological response functions; transport properties of the helical edge states; topological Mott insulators; many-body classification of topological insulators; critical properties of QSH phase transitions; transport properties of the 3D surface states; proximity effects between the QSH insulator to superconductors; and possible realization of QSH states in cold atom systems.
This workshop will primarily be organized around short talks leading to extended discussions, with only a few longer talks reserved for an overview or new, unpublished results. There will be ample time for thorough discussion, including some smaller, focus-group discussions. Strong preference will be given to applicants who can stay the full two weeks, although exceptions can be made for experimentalists.