Zhitenev NB, Fulton TA, Yacoby A, Hess HF, Pfeiffer LN, West KW
Bell Laboratories, Lucent Technologies, New Jersey 07974, USA.
Nature. 2000 Mar 30;404(6777):473-6. doi: 10.1038/35006591.
The concept of electron localization has long been accepted to be essential to the physics of the quantum Hall effect in a two-dimensional electron gas. The exact quantization of the Hall resistance and the zero of the diagonal resistance over a range of filling factors close to integral are attributed to the localization of electronic states at the Fermi level in the interior of the gas. As the electron density is changed, charging of the individual localized states may occur by single-electron jumps, causing associated oscillations in the local electrostatic potential. Here we search for such a manifestation of localized states in the quantum Hall regime, using a scanning electrometer probe. We observe localized potential signals, at numerous locations, that oscillate with changing electron density. In general, the corresponding spatial patterns are complex, but well-defined objects are often seen which evidently arise from individual localized states. These objects interact, and at times form a lattice-like arrangement.
长期以来，电子局域化的概念一直被认为是二维电子气中量子霍尔效应物理学的核心。在接近整数的一系列填充因子范围内，霍尔电阻的精确量子化以及对角电阻的零值归因于气体内部费米能级处电子态的局域化。随着电子密度的变化，单个局域态可能通过单电子跳跃进行充电，从而在局部静电势中引起相关振荡。在这里，我们使用扫描静电计探针在量子霍尔区域寻找这种局域态的表现形式。我们在许多位置观察到局域化的电势信号，这些信号随着电子密度的变化而振荡。一般来说，相应的空间图案很复杂，但经常能看到明显由单个局域态产生的明确物体。这些物体相互作用，有时形成类似晶格的排列。
