Fractional quantum Hall effect in a dilute magnetic semiconductor
Fractional quantum Hall effect in a dilute magnetic semiconductor
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稀磁半导体中的分数量子霍尔效应
DOI：
10.1103/physrevb.90.115302
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发表时间：
2014
影响因子：
3.7
通讯作者：
D. Weiss
中科院分区：
文献类型：
--
作者：
C. Betthausen;P. Giudici;A. Iankilevitch;C. Preis;V. Kolkovsky;M. Wiater;G. Karcezwski;B.A. Piot;J. Kunc;M. Potemski;T. Wojotowicz;D. Weiss
本文报道了在稀磁半导体中二维电子系统(2DES)的最低朗道能级中观察到的分数量子霍尔效应。磁性杂质的存在导致了巨大的塞曼分裂，导致了复合费米子朗道能级的异常有序。在实验中，这导致了填充因子周围分数间隙的非常规开启和闭合，这是面内磁场的函数，即塞曼能量的函数。通过在复合朗道能级谱中加入交换能量，可以定量地模拟能隙在填充因子处的开启和关闭。稀磁2DES中广泛可调的自旋分裂为控制分数态提供了一种手段。
We report the observation of the fractional quantum Hall effect in the lowest Landau level of a two-dimensional electron system (2DES), residing in the diluted magnetic semiconductor. The presence of magnetic impurities results in a giant Zeeman splitting leading to an unusual ordering of composite fermion Landau levels. In experiment, this results in an unconventional opening and closing of fractional gaps around the filling factoras a function of an in-plane magnetic field, i.e., of the Zeeman energy. By including thes-dexchange energy into the composite Landau level spectrum the opening and closing of the gap at filling factorcan be modeled quantitatively. The widely tunable spin-splitting in a diluted magnetic 2DES provides a means to manipulate fractional states.