Study of Quantum Transport in Low Dimensional Electrons in Superperiodic Structures

超周期结构中低维电子的量子输运研究

基本信息

批准号：
06402011
负责人：
IYE Yasuhiro
金额：
$ 13.31万
依托单位：
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：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

项目摘要

The band theory which constitutes the basis of solid state physics, is essentially a description of the behavior of electrons in periodic potential. In this research project, we have investigated transport phenomena that originate from superperiodic structures. The materials investigated are natural and artificial layred materials including organic conductors, graphite interacalation compounds, semiconductor superlattices and metallic multilayrs. We also studied two-dimensional electron system at the interface of semiconductors with microstructured gate electrode. The superconducting magnet system purchased with this grant has been also effectively used in studies of diluted magnetic semiconductors.The followings are the main research acomplishments :By fabricating GaAs/AlGaAs heterostructures with microstructured ferromagnetic gate electrode on the surface, we have succeeded in applying spatially modulated magnatic field to two-dimensional electron gas. We predicted earlier that in a unidirectional modulation of magnetic field. the magnetoresistance shows commensurability oscillation effect. which we have experimentally verified in this research term.Angular-dependent magnetoresistance oscillation (ADMRO) is a phenomenon discovered in (BEDT-TTF)-based organic conductors. We have shown theoretically that it is a generic property of quasi-two-dimensional Fermi surface, and experimentally verified it by observing the ADMRO in graphite intercalation compounds and also in GaAs/AlGaAs superlattice.(BEDT-TTF)2KHg(SCN)4 exhibits a different type of ADMRO.We have clarified that it originates from the commensurability of open orbits on a quasi-one dimensional Fermi surface with the underlying unit cell by mapping of the resistivity dips from two-axis rotation measurement and by model calculations.

构成固态物理基础的频带理论实质上是对周期潜力中电子行为的描述。在该研究项目中，我们研究了源自超周期结构的运输现象。研究的材料是天然和人造的材料，包括有机导体，石墨间间化合物，半导体超晶格和金属多层。我们还研究了与微结构栅极电极的半导体界面的二维电子系统。用这笔赠款购买的超导磁铁系统也有效地用于稀释的磁性半导体的研究中。以下是主要的研究结果：通过在地面上制造具有微结构铁电磁栅极电极的GAAS/AlgaAS异质结构，我们已经成功地将磁场磁场施加到两二极性电子中。我们早些时候预测，在磁场的单向调制中。磁磁性显示出相当性的振荡效果。我们已经在本研究术语中对其进行了实验验证。依赖性的磁阻振荡（ADGRO）是在基于（BEDTT-TTF）的有机导体中发现的现象。 We have shown theoretically that it is a generic property of quasi-two-dimensional Fermi surface, and experimentally verified it by observing the ADMRO in graphite intercalation compounds and also in GaAs/AlGaAs superlattice.(BEDT-TTF)2KHg(SCN)4 exhibits a different type of ADMRO.We have clarified that it originates from the commensurability of open orbits on a quasi-one尺寸的费米表面具有基础单元，通过映射电阻率从两轴旋转测量和模型计算中绘制。