圧力でグラフェンモアール超網のダイナミック・バンド・ストラクチャー・チューニング
Matthew Yankowitz1, Jeil Jung2, Evan Laksono3,4
1Department of Physics, Columbia University, New York, NY, USA.
Nature
|May 18, 2018
まとめ
研究者は,静水圧を適用することによって,ヴァン・デル・ワールスの異質構造の電子特性を動的に調節しました. この圧力誘発のチューニングは,グラフェン・ボロン・ニトリド装置のバンドギャップとゲートカップリングを大幅に変化させた.
科学分野:
- 凝縮物質物理学
- 材料科学
- ナノテクノロジー
背景:
- ヴァン・デル・ワールスのヘテロ構造は,層間の相互作用によりユニークな電子特性を提供します.
- 層間結合の強さは決定的に重要ですが,決定するのが困難で,固定されていることが多い.
研究 の 目的:
- ヴァン・デル・ワールスの異質構造における層間分離の制御可能な調整を実証する.
- 電子特性とバンド構造に対する水立圧の影響を調査する.
主な方法:
- グラフェン・ボロン・ナトリドヘテロ構造の層間分離を調整するために水立圧力を利用した.
- バンドギャップとキャパシティブゲートカップルの変化を測った.
- 原子スケールの構造的変形を理解するために理論的なモデリングを使用しました.
主要な成果:
- 液圧制御で調整されたインターレイヤ分離,電子特性を変更する.
- 圧力の増加に伴って モアール・スーパー・グリッドによる 帯差の超線形増加を観測した.
- 容量ゲートカップリングの大幅な増加 (最大25%) を報告した.
結論:
- 静水圧は,ヴァン・デル・ワールスのヘテロ構造をチューニングするためのダイナミックな方法を提供します.
- 圧力と回転順を組み合わせることで 動的バンド構造の設計が可能になる.
- 原子スケールの構造変形は重要な役割を果たし,圧力によって修正されます.
関連する概念動画
02:35Band Theory
17.3K
When two or more atoms come together to form a molecule, their atomic orbitals combine and molecular orbitals of distinct energies result. In a solid, there are a large number of atoms, and therefore a large number of atomic orbitals that may be combined into molecular orbitals. These groups of molecular orbitals are so closely placed together to form continuous regions of energies, known as the bands.
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
17.3K
01:24Static, Stagnation, Dynamic and Total Pressure
1.5K
The concept of static, stagnation, dynamic, and total pressure is fundamental in fluid dynamics, often explained using Bernoulli's equation:
1.5K
02:34Vapor Pressure
41.0K
When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor...
41.0K
01:01Energy Bands in Solids
2.0K
Isolated atoms have discrete energy levels that are well described by the Bohr model. And, it quantifies the energy of an electron in a hydrogen atom as En. Higher quantum numbers 'n' yield less negative, closer electron energy levels.
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
2.0K
01:04Problem-Solving: Tuning of a Guitar String
1.1K
In the case of stringed instruments like the guitar, the elastic property that determines the speed of the sound produced is its linear mass density or the mass per unit length. This is simply called the linear density. If the string's linear density is constant along the string, then the linear density is simply the total mass divided by the total length.
The string's wave speed can be regulated by varying the linear density. Tension is the other property that determines the speed of...
The string's wave speed can be regulated by varying the linear density. Tension is the other property that determines the speed of...
1.1K
03:28Vapor Pressure Lowering
31.4K
The equilibrium vapor pressure of a liquid is the pressure exerted by its gaseous phase when vaporization and condensation are occurring at equal rates:
31.4K