The main focus of our research is the exotic collective behavior of low dimensional
electronic systems. Of special interest are single- and multilayer
two-dimensional electron systems in ultra-clean GaAs/AlGaAs heterostructures grown by
molecular beam epitaxy (MBE) and single and few-layer graphene. Experimental probes include
electrical and thermal transport, tunneling spectroscopy, NMR, surface acoustic waves, and
thermodynamic measurements at low temperatures (down to 15mK) and high magnetic fields
(up to 16 Tesla).
Two-dimensional electron systems have been the source of some of the most spectacular discoveries in physics over the last 25 years. The integer and fractional quantized Hall effects are perhaps the best known, but dramatic findings continue to be made. For example, in conventional single layer 2D systems, recent research of our and other groups have revealed the existence of a whole new class of 2D electronic phases that resemble molecular liquid crystals. There is also a growing body of experimental evidence suggesting that under appropriate conditions, a double layer 2D electron system can condense into a remarkable new kind of superfluid state. This new state is analogous to a superconductor, only the "Cooper pairs" are excitons which consist of an electron in one layer bound to a hole in the other. Even more recently, the advent of graphene, a single atomic layer of carbon, has opened a new chapter in low dimensional electron physics. From relativistic energy dispersions to externally tunable energy gaps, graphene and its few-layer cousins offer new opportunities for both fundamental physics and device applications.