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Phase diagram of the integer quantum Hall effect in p-type Germanium

M. Hilke·D. Shahar·S. H. Song·D. C. Tsui·Y. H. Xie
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Abstract

We experimentally study the phase diagram of the integer quantized Hall effect, as a function of density and magnetic field. We used a two dimensional hole system confined in a Ge/SiGe quantum well, where all energy levels are resolved, because the Zeeman splitting is comparable to the cyclotron energy. At low fields and close to the quantum Hall liquid-to-insulator transition, we observe the floating up of the lowest energy level, but NO FLOATING of any higher levels, rather a merging of these levels into the insulating state. For a given filling factor, only direct transitions between the insulating phase and higher quantum Hall liquids are observed as a function of density. Finally, we observe a peak in the critical resistivity around filling factor one.

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M. Hilke, D. Shahar, S. H. Song, D. C. Tsui, Y. H. Xie. 1999-09-28. Phase diagram of the integer quantum Hall effect in p-type Germanium. https://doi.org/10.1103/physrevb.62.6940

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