Large conductance anisotropy in a novel two‐dimensional electron system grown on vicinal (111)B GaAs with multiatomic steps
Large conductance anisotropy in a novel two‐dimensional electron system grown on vicinal (111)B GaAs with multiatomic steps
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采用多原子步骤在邻位 (111)B GaAs 上生长的新型二维电子系统中的大电导各向异性
DOI：
10.1063/1.117829
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发表时间：
1996
影响因子：
4
通讯作者：
H. Sakaki
中科院分区：
文献类型：
--
作者：
Yusui Nakamura;S. Koshiba;H. Sakaki
在邻近的（111）B衬底上成功地形成了一种新的选择性掺杂AlGaAs/GaAs异质结，其中引入了平均间距为~ 20 nm的准周期和非周期多原子步骤。研究发现，两维电子在台阶上的电导G⊥远低于沿台阶的G∥，在18k时，G∥/G⊥的比值超过100。虽然G∥几乎与温度T在~ 70 K以下无关，但G⊥以1/T呈指数增长，活化能为~ 5 meV，表明电子在非周期步骤中的运动存在潜在障碍。
A novel selectively doped AlGaAs/GaAs heterojunction was successfully formed on a vicinal (111)B substrate, in which both quasiperiodic and aperiodic multiatomic steps with the average spacings of ∼20 nm are introduced. It is found that the electrical conductance G⊥ of two‐dimensional electrons across the steps is far lower than that of G∥ along the steps and the ratio G∥/G⊥ exceeds 100 at 18 K. While G∥ is almost independent of temperature T below ∼70 K, G⊥ increases exponentially with 1/T with the activation energy of ∼5 meV, indicating the presence of potential barriers for the electron motion across the aperiodic steps.