Size determination of InAs quantum dots using magneto-tunnelling experiments
Size determination of InAs quantum dots using magneto-tunnelling experiments
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使用磁隧道实验确定 InAs 量子点的尺寸
DOI：
10.1088/0268-1242/14/11/104
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发表时间：
1999
影响因子：
1.9
通讯作者：
F. Ahlers
中科院分区：
文献类型：
--
作者：
I. Hapke;U. Zeitler;H. Schumacher;R. Haug;K. Pierz;F. Ahlers
通过在AlAs势垒中嵌入InAs的GaAs-AlAs-GaAs结构的隧穿实验显示了电流-电压特性的步骤，我们将其分配给两个三维电极之间自组装InAs量子点的单电子隧穿。从电流阶跃开始时的磁场依赖性出发，我们确定了电子波函数在点中的横向扩展到4 nm，对应于直径为14 nm的点。在更高电压下的步骤复制归因于通过带电点的隧穿。通过透射电子显微镜和原子力显微镜分别在GaAs表面和AlAs表面上具有InAs点的对照样品上测量了相似的结构点尺寸。
Tunnelling experiments through GaAs-AlAs-GaAs structures with InAs embedded in the AlAs barrier show steps in the current-voltage characteristics which we assign to single-electron tunnelling through self-assembled InAs quantum dots between two three-dimensional electrodes. From the magnetic field dependence of the onset of the current steps, we determine the lateral extension of the electronic wave function in the dot to 4 nm, corresponding to a dot of 14 nm in diameter. Replica of steps at higher voltages are attributed to tunnelling through charged dots. A similar structural dot size is measured independently by transmission electron microscopy on the same wafer and by atomic force microscopy on control samples with InAs dots on a GaAs or an AlAs surface, respectively.