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arXiv · cond-mat/9711158

Impurity Effects and Spin Polarizations in a Narrow Quantum Hall System

Tapash Chakraborty·K. Niemelä·P. Pietiläinen
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Abstract

The temperature dependence of electron spin polarization for a narrow quantum Hall system shows behavior analogous to that of a two-dimensional system at major filling factors. At the lowest half-filled quantum Hall state for which no two-dimensional analog exists, we find a stable spin partially-polarized system. Periodic Gaussian repulsive impurities (antidots) in such a system leads to novel spin transitions at $ν=\frac13$ and $ν=\frac12$ and the pair-correlation functions provide clues about nature of different ground states in the system. These results can be explored in optical spectroscopy and optically pumped NMR Knight shift measurements.

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Tapash Chakraborty, K. Niemelä, P. Pietiläinen. 1997-11-17. Impurity Effects and Spin Polarizations in a Narrow Quantum Hall System. https://doi.org/10.1103/physrevb.58.9890

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