arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0908.2360cond-mat.mes-hallcond-mat.str-el
收藏

空穴量子点接触中局域化和0.7反常的证据

Evidence for localization and 0.7 anomaly in hole quantum point contacts

Y. Komijani, M. Csontos, I. Shorubalko, T. Ihn, K. Ensslin, Y. Meir, D. Reuter, A. D. Wieck

摘要:

利用低温电导谱技术研究了p型GaAs/AlGaAs异质结中的量子点接触。除了以$2e^{2}/h$为单位的一维电导量子化之外,在大约$0.7(2e^{2}/h)$处发现了一个明显的额外平台,该平台具有从n型样品的实验中已知的所谓“0.7异常”的特征性质。在高垂直磁场中0.7平台的演化揭示了准定域态的存在,并支持了基于自洽电荷定域的0.7反常解释。当施加横向电场时,这些观测结果是稳健的,该横向电场移动了量子点接触中电子波函数的相对位置,证明了底层物理的内在本质。

英文摘要:

Quantum point contacts implemented in p-type GaAs/AlGaAs heterostructures are investigated by low-temperature electrical conductance spectroscopy measurements. Besides one-dimensional conductance quantization in units of $2e^{2}/h$ a pronounced extra plateau is found at about $0.7(2e^{2}/h)$ which possesses the characteristic properties of the so-called "0.7 anomaly" known from experiments with n-type samples. The evolution of the 0.7 plateau in high perpendicular magnetic field reveals the existence of a quasi-localized state and supports the explanation of the 0.7 anomaly based on self-consistent charge localization. These observations are robust when lateral electrical fields are applied which shift the relative position of the electron wavefunction in the quantum point contact, testifying to the intrinsic nature of the underlying physics.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑