SrTiO3上のグラフェンのヘリカル量子ハール相
Louis Veyrat1, Corentin Déprez1, Alexis Coissard1
1Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France.
まとめ
研究者はストロンチウムチタネート基板を使用してグラフェンでトポロジカルフェーズを達成し,頑丈な螺旋的なエッジ輸送を可能にしました. この画期的な発見は スピントロニクスと トポロジカル量子計算の扉を開きます
科学分野:
- 凝縮物質物理学
- 材料科学
背景:
- 磁場下のグラフェンの基本状態は,理論的には量子ホールのトポロジック断熱体であると予測されました.
- 実験的観測は,理論的な予測とは異なる格子相互作用による絶縁状態を示すことが多い.
研究 の 目的:
- 予測されたトポロジカル・フェーズをグラフェンで実験的に実現する.
- この段階の達成における クーロン相互作用スクリーニングの役割を調査する.
主な方法:
- ストロンチウムチタネート (SrTiO3) 基板を用いて,グラフェンのクーロン相互作用をスクリーニングする.
- 垂直磁場を使って グラフェンのランдауレベルを調整する
主要な成果:
- グラフェンの基底状態で トポロジカル・フェーズを達成した.
- 低磁場 (1テスラ) と高温 (110Kまで) でミクロン長さの距離で頑丈な螺旋のエッジ輸送を観測した.
結論:
- グラフェンのトポロジカルな量子ホールの断熱状態にアクセスする方法を実証した.
- 開発されたグラフェンプラットフォームは,スピントロニクスとトポロジカル量子コンピューティングアプリケーションに希望を示しています.
関連する概念動画
Hybridization of Atomic Orbitals I
64.7K
The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically accomplished by the linear combination of atomic orbitals. The new orbitals that...
64.7K
Hybridization of Atomic Orbitals II
47.1K
sp3d and sp3d 2 Hybridization
47.1K
Chirality at Nitrogen, Phosphorus, and Sulfur
6.7K
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
6.7K
The Hall Effect
3.8K
Edwin H. Hall, in the year 1879, devised an experiment that could be used to identify the polarity of the predominant charge carriers in a conducting material. From a historical perspective, this experiment was the first to demonstrate that the charge carriers in most metals are negative.
3.8K
Crystal Field Theory - Tetrahedral and Square Planar Complexes
47.6K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
47.6K
π Electron Effects on Chemical Shift: Overview
1.5K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.5K


