II. Physikalisches Institut B and JARA-FIT, RWTH Aachen University, 52074 Aachen, Germany.
Phys Rev Lett. 2011 Apr 15;106(15):156805. doi: 10.1103/PhysRevLett.106.156805. Epub 2011 Apr 13.
Using low-temperature scanning tunneling spectroscopy applied to the Cs-induced two-dimensional electron system (2DES) on p-type InSb(110), we probe electron-electron interaction effects in the quantum Hall regime. The 2DES is decoupled from bulk states and exhibits spreading resistance within the insulating quantum Hall phases. In quantitative agreement with calculations we find an exchange enhancement of the spin splitting. Moreover, we observe that both the spatially averaged as well as the local density of states feature a characteristic Coulomb gap at the Fermi level. These results show that electron-electron interaction can be probed down to a resolution below all relevant length scales.
利用低温扫描隧道光谱学研究 Cs 诱导的 p 型 InSb(110)二维电子系统（2DES），我们在量子 Hall 区探测电子-电子相互作用效应。2DES 与体相状态解耦，并在绝缘量子 Hall 相中表现出扩展电阻。我们发现，自旋劈裂的交换增强与计算结果定量一致。此外，我们观察到，在费米能级处，空间平均和局域态密度都具有特征的库仑能隙。这些结果表明，电子-电子相互作用可以探测到低于所有相关长度尺度的分辨率。
