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Quantum Phase Transitions in the p-SiGe system

P. T. Coleridge·P. Zawadzki·A. Sachrajda·Y. Feng·R. L. Williams
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Abstract

The rich variety of phase transitions observed in the strained p-SiGe system are considered and compared. It is shown that the integer quantum Hall effect transitions, the Hall insulating transition and the re-entrant transition into an insulating phase near filling factor 3/2 are all very similar and good examples of quantum critical phase transitions. The B=0 metal insulator transition also shows many similarities to these transitions but requires the inclusion of an extra impurity scattering term to fully explain the data.

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P. T. Coleridge, P. Zawadzki, A. Sachrajda, Y. Feng, R. L. Williams. 1999-09-20. Quantum Phase Transitions in the p-SiGe system. https://arxiv.org/abs/cond-mat/9909292

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