石墨烯磁性量子点能级上的阿哈诺夫-玻姆通量和双间隙效应

IF 2.8 3区 物理与天体物理 Q2 PHYSICS, CONDENSED MATTER
Fatima Belokda , Ahmed Bouhlal , Ahmed Siari , Ahmed Jellal
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引用次数: 0

摘要

为了回答这个问题,我们考虑了在磁场 B 诱导下并受到两种不同间隙(内部间隙 Δ1和外部间隙 Δ2)影响的石墨烯磁性量子点(GMQDs)。在确定特征旋光子并确保 GMQD 边界的连续性之后,我们提出了描述相应能级的解析方程。我们的结果表明,能级可以表现出对称或不对称的行为,这取决于K(τ=1)和K′(τ=-1)以及量子角动量m。当带隙存在于外部时,这种影响就不那么明显了,从而导致约束电子态的寿命延长。进一步增大 ΦAB 会减少导带和价带之间的电平数,从而增大带隙。这些结果表明,石墨烯的电子特性可以通过 AB 通量的存在进行调整,从而为控制基于石墨烯的量子器件的行为提供了可能。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Aharonov–Bohm flux and dual gaps effects on energy levels in graphene magnetic quantum dots
We address the question of how the Aharonov–Bohm flux ΦAB can affect the energy levels of graphene magnetic quantum dots (GMQDs) of radius R. To answer this question, we consider GMQDs induced by a magnetic field B and subjected to two different gaps — an internal gap Δ1 and an external gap Δ2. After determining the eigenspinors and ensuring continuity at the boundary of the GMQDs, we formulate an analytical equation describing the corresponding energy levels. Our results show that the energy levels can exhibit either a symmetric or an asymmetric behavior depending on the valleys K(τ=1) and K(τ=1) together with the quantum angular momentum m. In addition, we find that ΦAB causes an increase in the band gap width when Δ1 is present inside the GMQDs. This effect is less significant when a gap is present outside, resulting in a longer lifetime of the confined electronic states. Further increases in ΦAB reduce the number of levels between the conduction and valence bands, thereby increasing the band gap. These results demonstrate that the electronic properties of graphene can be tuned by the presence of the AB flux, offering the potential to control the behavior of graphene-based quantum devices.
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来源期刊
Physica B-condensed Matter
Physica B-condensed Matter 物理-物理:凝聚态物理
CiteScore
4.90
自引率
7.10%
发文量
703
审稿时长
44 days
期刊介绍: Physica B: Condensed Matter comprises all condensed matter and material physics that involve theoretical, computational and experimental work. Papers should contain further developments and a proper discussion on the physics of experimental or theoretical results in one of the following areas: -Magnetism -Materials physics -Nanostructures and nanomaterials -Optics and optical materials -Quantum materials -Semiconductors -Strongly correlated systems -Superconductivity -Surfaces and interfaces
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