The discovery of the quantum Hall effect (QHE) is a remarkable achievement in condensed matter physics awarded with two Nobel prizes. At low temperatures and in strong magnetic fields, it is found that the Hall resistance of a two dimensional electron system has plateaus as a function of the number of electrons. In the integer quantum Hall effect (IQHE), the Hall resistance at the plateaus turns out to be R=h/ne², where n is an integer. In the fractional quantum Hall effect (FQHE), n can be a fractional number. Apart from the fundamental interest of these highly correlated systems, due to the high precision of the measurement, the quantization of the Hall resistance is now used as the standard of resistance.
Some representative publications:
Skyrme crystal versus Skyrme liquid, Paredes, B.; Palacios, J. J., Physical Review B 60, 15570-15573 (1999).
Numerical tests of the chiral Luttinger liquid theory for fractional Hall edges, Palacios, J. J.; MacDonald, A. H., Physical Review Letters 76, 118-121 (1996).
Signature of quantum Hall effect Skyrmions in tunneling: A theoretical study, Palacios, J. J.; Fertig, H. A., Physical Review Letters 79, 471-474 (1997).