Publications

Quantization of the diagonal resistance: Density gradients and the empirical Resistance rule in a 2D system

Pan, Wei P.; Xia, J.S.; Stormer, H.L.; Tsui, D.C.; Vicente, C.L.; Adams, E.D.; Sullivan, N.S.; Pfeiffer, L.N.; Baldwin, K.W.; West, K.W.

We have observed quantization of the diagonal resistance, Rxx, at the edges of several quantum Hall states. Each quantized Rxx value is close to the difference between the two adjacent Hall plateaus in the off-diagonal resistance, Rxy. Peaks in Rxx occur at different positions in positive and negative magnetic fields. Practically all Rxx features can be explained quantitatively by a 1%/cm electron density gradient. Therefore, Rxx is determined by Rxy and unrelated to the diagonal resistivity ρxx. Our findings throw an unexpected light on the empirical resistivity rule for 2D systems. © 2005 The American Physical Society.