Device Physics of Strongly Correlated Semiconductor

强相关半导体器件物理

• 批准号: 13440109
• 负责人: TAKAGI Hidenori
• 金额: $ 9.86万
• 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 (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440109/
• 关键词: Mott insulator; physics of Semiconductor Devices; Carrier Doping; nano-scale variation of electronic; charge ordering; Field Effect Transistor (FET) Structure; transition metal oxides.; 電荷効果トランジスタ; モット半導体; キャリアドーピグ; Ca_<2-x>Na_xCuO_2Cl_2; 電界効果型

The aim of this research project is to explore the device physics of strongly correlated semiconductors. One of the major targets was the impurity effect. As a prototypical system, lightly doped Mott insulator Ca_<2-x>Na_xCuO_2Cl_2 was studied. We found a non-scale self-organization of electrons associated with doping by STM/STS and finally identified it as a checkerboard type charge ordering, which we believe is at the heart of cuprate physics including large psedo-gap phenomena. We also find nano-scale variation of electronic states around the impurities in nearly ferromagnetic ruthenates, which represents an important step to establish physics of impurity states in strongly correlated electron systems. The other major targets was fabrication of oxide device, in particular field effect transistor (FET). We have successfully fabricated SrTiO_3 perovskite FET, which shows well defined FET characteristics such as the saturation of drain current. Even better performance was achieved in another perovskite oxide KTaO_3, which showed ON/OFF rationof 1000 and the field effect mobility of 0.4 cm^2/Vsec comparable with those of organic FET. These devices can work at a cryogenic temperature as low as 2K and the presence of metallic channel was confirmed. These results opened door for FET "chemistry" of exotic transition metal oxides.

该研究项目的目的是探索密切相关的半导体的设备物理学。主要目标之一是杂质效应。作为一个典型的系统，研究了轻轻掺杂的Mott绝缘子CA__ <2-X> Na_xcuo_2cl_2。我们发现了与STM/STS掺杂相关的电子的非规模自组织，并最终将其确定为棋盘型型电荷顺序，我们认为这是Cuprate Physics的核心，包括大型PSEDO-GAP现象。我们还发现电子状态在几乎铁磁鲜明的杂质周围的纳米级变化，这代表了建立在强相关的电子系统中的杂质态物理物理学的重要步骤。另一个主要目标是制造氧化物装置，特别是田间效应晶体管（FET）。我们已经成功地制造了SRTIO_3钙钛矿FET，该FET显示出明确定义的FET特性，例如排水电流的饱和度。在另一个钙钛矿氧化物KTAO_3中实现了更好的性能，该氧化盐氧化物ktao_3持续/关闭1000，而现场效应迁移率与有机FET的eartion氧化氧化物_3 _3实现了0.4 cm^2/vsec。这些设备可以在低至2K的低温温度下工作，并确认金属通道的存在。这些结果为外来过渡金属氧化物的FET“化学”打开了大门。

项目成果

Katsufuji T et al.: "Coupling between magnetism and dielectric properties in quantum paraelectric EuTiO_3"PHYS REV B. 64・05. 4415-4418 (2001)

Katsufuji T 等人：“量子顺电 EuTiO_3 中的磁性与介电特性之间的耦合” PHYS REV B. 4415-4418 (2001)。

Katsufuji T et al.: "Dielectric and magnetic anomalies and spin frustration in hexagonal RMnO_3 (R = Y, Yb, and Lu)"PHYS REV B. 64-10. 4419-4422 (2001)

Katsufuji T 等人：“六方 RMnO_3（R = Y、Yb 和 Lu）中的介电和磁异常以及自旋挫败”PHYS REV B. 64-10。

Yuhki Kohsaka, Masaki Azuma Ikuya Yamada, Takao Sasagawa, Tetsuo Hanaguri, Mikio Takano, Hidenori Takagi: "Growth of Na-Doped Ca_2CuO_2Cl_2 Single Crystals under High Pressures of Several GPa"J.Am.Chem.Soc. Vol.124, No.41. 12275-12278 (2002)

Yuhki Kohsaka、Masaki Azuma Ikuya Yamada、Takao Sasakawa、Tetsuo Hanaguri、Mikio Takano、Hidenori Takagi：“在几 GPa 的高压下生长 Na 掺杂 Ca_2CuO_2Cl_2 单晶”J.Am.Chem.Soc。

Ueda H, Kitazawa K, Matsumoto T, Takagi H: "Charge transport near pressure-induced antiferromagnetic quantum critical point in Magneli-phase vanadium oxides"Solid State Communications. 125:(2). 83-87 (2003)

Ueda H、Kitazawa K、Matsumoto T、Takagi H：“Magneli 相钒氧化物中压力诱导反铁磁量子临界点附近的电荷传输”固态通信。

Matsuno K, et al.: "Charge ordering in the geometrically frustrated spinel AIV_2O_4"J PHYS SOC JPN. 70・6. 1456-1459 (2001)

Matsuno K 等人：“几何挫败尖晶石 AIV_2O_4 中的电荷排序”J PHYS SOC JPN 70・6（2001）。