Extreme Sensitivity of the Spin-Splitting and 0.7 Anomaly to Confining Potential in One-Dimensional Nanoelectronic Devices
详细信息 查看全文
- 作者：A. M. Burke ; O. Klochan ; I. Farrer ; D. A. Ritchie ; A. R. Hamilton ; A. P. Micolich
- 刊名：Nano Letters
- 出版年：2012
- 出版时间：September 12, 2012
- 年：2012
- 卷：12
- 期：9
- 页码：4495-4502
- 全文大小：498K
- 年卷期：v.12,no.9(September 12, 2012)
- ISSN：1530-6992
文摘
Quantum point contacts (QPCs) have shown promise as nanoscale spin-selective components for spintronic applications and are of fundamental interest in the study of electron many-body effects such as the 0.7 脳 2e2/h anomaly. We report on the dependence of the 1D Land茅 g-factor g* and 0.7 anomaly on electron density and confinement in QPCs with two different top-gate architectures. We obtain g* values up to 2.8 for the lowest 1D subband, significantly exceeding previous in-plane g-factor values in AlGaAs/GaAs QPCs and approaching that in InGaAs/InP QPCs. We show that g* is highly sensitive to confinement potential, particularly for the lowest 1D subband. This suggests careful management of the QPC鈥檚 confinement potential may enable the high g* desirable for spintronic applications without resorting to narrow-gap materials such as InAs or InSb. The 0.7 anomaly and zero-bias peak are also highly sensitive to confining potential, explaining the conflicting density dependencies of the 0.7 anomaly in the literature.