New approach to the physics of two dimensional electron systems

二维电子系统物理学的新方法

• 批准号: 21244047
• 负责人: OKAMOTO Tohru
• 金额: $ 30.04万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21244047/
• 关键词: 表面・界面; 低温物性; 表面物性; 表面・界面物性; 半導体物性; 強相関電子系

We study magnetotransport in a high-mobility Si two-dimensional electron system by in situ tilting of the sample relative to the magnetic field. A pronounced dip in the longitudinal resistivity is observed during the Landau-level crossing process for noninteger filling factors. This indicates that electrons in the relevant Landau levels become localized at the coincidence.Cyclotron resonance of two-dimensional electrons is studied at low temperatures for a high-mobility Si/SiGe which exhibits a metallic temperature dependence of dc resistivity. The relaxation time shows a negative temperature dependence, which is similar to that of the transport scattering time.Two-dimensional (2D) superconductivity was studied by magnetotransport measurements on single-atomic-layer Pb films on a cleaved GaAs surface. The results are explained in terms of an inhomogeneous superconducting state predicted for 2D metals with a large Rashba spin splitting.

我们通过将样品相对于磁场的原位倾斜来研究高慢速Si二维电子系统中的磁转移。对于非智能填充因子的Landau级穿越过程，观察到纵向电阻率的明显倾角。这表明相关Landau水平的电子在巧合的位置。二维电子在低温下进行了二维电子的共振，以具有高弹性Si/SIGE，其表现出DC电阻的金属温度依赖性。松弛时间显示出负温度的依赖性，与传输散射时间相似。通过磁通转移测量值在切断的GAAS表面上的单原子层PB膜上进行了磁转移测量，研究了两次二维（2D）超导性。结果是用预测的2D金属的不均匀超导状态来解释的，该状态具有较大的Rashba自旋分裂。

项目成果

Superconductivity of ultrathin metallic films on cleaved GaAs surfaces

解理 GaAs 表面超薄金属薄膜的超导性

• 发表时间: 2012
• 作者: T. Sekihara;R. Masutomi;and T. Okamoto
• 通讯作者: and T. Okamoto

Well-width dependence of valley splitting in Si/SiGe quantum wells

Si/SiGe 量子阱中谷分裂的阱宽依赖性

• DOI: 10.1063/1.3270539
• 发表时间: 2009
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: K. Sasaki;R. Masutomi;K. Toyama;K. Sawano;Y. Shiraki;and T. Okamoto
• 通讯作者: and T. Okamoto

Recent publications (Okamoto group)

最近发表的文章（冈本组）

Electrical Detection of Electron-Spin Resonance in Two-Dimensional Systems, Series : the Topic in Applied Physics, Vol.115

二维系统中电子自旋共振的电检测，系列：应用物理学主题，第 115 卷

• 作者: 野田幸男;石川喜久;李彰煕;金信愛;文明國;J. Matsunami and T. Okamoto
• 通讯作者: J. Matsunami and T. Okamoto

Hysteresis in magnetoresistance of InAs surface inversion layers covered with submonolayer of Fe films

亚单层 Fe 薄膜覆盖的 InAs 表面反型层的磁阻磁滞

• 发表时间: 2009
• 作者: T.Mochizuki;R.Masutomi;T.Okamoto
• 通讯作者: T.Okamoto