The Search for Quantum Anomalous Hall Insulators

David Vanderbilt
Monday, October 16, 2017 - 4:30pm to 5:30pm

The quantum Hall effect, discovered 35 years ago, is a bizarre phenomenon in which a 2D gapped system can nevertheless carry a current.  Moreover, the transverse conductivity of the system is precisely quantized in units of e^2/h.  Unfortunately, this behavior requires a strong perpendicular magnetic field, and has only been observed at low temperatures.  Work of Haldane in 1988 raised the possibility that similar physics could be observed in two-dimensional magnetic systems without any external magnetic field, and potentially at much higher temperatures.  Such a system is known as a "...