Experimental evidence for a two-dimensional quantized Hall insulator

Article

关键词: 2-DIMENSIONAL ELECTRON-SYSTEM;    TRANSITION;    LIQUID;    COEFFICIENT;    DUALITY;    PHASE;    GAS;   

DOI  :  10.1038/27160

来源: SCIE

【 摘 要 】

The general theoretical definition of an insulator is a material in which the conductivity vanishes at the absolute zero of temperature. In classical insulators, such as materials with a band gap, vanishing conductivities lead to diverging resistivities. But other insulators can show more complex behaviour, particularly in the presence of a high magnetic field, where different components of the resistivity tensor can display different behaviours: the magnetoresistance diverges as the temperature approaches absolute zero, but the transverse (Hall) resistance remains finite. Such a system is known as a Hall insulator(1). Here we report experimental evidence for a quantized(2) Hall insulator in a two-dimensional electron system-confined in a semiconductor quantum well. The Hall resistance is quantized in the quantum unit of resistance h/e(2),, where h is Planck's constant and e the electronic charge. At low fields, the sample reverts to being a normal Hall insulator.

【 授权许可】

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