Mouhamadou Hassane Saley , Abderrahim El Mouhafid , Ahmed Jellal
{"title":"双选通条件下垂直磁场对双层石墨烯的影响","authors":"Mouhamadou Hassane Saley , Abderrahim El Mouhafid , Ahmed Jellal","doi":"10.1016/j.physe.2024.116077","DOIUrl":null,"url":null,"abstract":"<div><p>By studying the impact of a perpendicular magnetic field <span><math><mi>B</mi></math></span> on AB-bilayer graphene (AB-BLG) under dual gating, we yield several key findings for the ballistic transport of gate <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span>. Firstly, we discover that the presence of <span><math><mi>B</mi></math></span> leads to a decrease in transmission. At a high value of <span><math><mi>B</mi></math></span>, we notice the occurrence of anti-Klein tunneling over a significant area. Secondly, in contrast to the results reported in the literature, where high peaks were found with an increasing in-plane pseudomagnetic field applied to AB-BLG, we find a decrease in conductivity as <span><math><mi>B</mi></math></span> increases. However, it is worth noting that in both cases, the number of oscillations decreases compared to the result in the study where no magnetic field was present <span><math><mrow><mo>(</mo><mi>B</mi><mo>=</mo><mn>0</mn><mo>)</mo></mrow></math></span>. Thirdly, at the neutrality point, we demonstrate that the conductivity decreases and eventually reaches zero for a high value of <span><math><mi>B</mi></math></span>, which contrasts with the result that the conductivity remains unchanged regardless of the value taken by the in-plane field. Finally, we consider the diffusive transport with gate <span><math><mrow><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>2</mn><msub><mrow><mi>γ</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> and observe two scenarios. The amplitude of conductivity oscillations increases with <span><math><mi>B</mi></math></span> for energy <span><math><mi>E</mi></math></span> less than <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> but decreases in the opposite case <span><math><mrow><mi>E</mi><mo>></mo><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></mrow></math></span>.</p></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"165 ","pages":"Article 116077"},"PeriodicalIF":2.9000,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effect of a perpendicular magnetic field on bilayer graphene under dual gating\",\"authors\":\"Mouhamadou Hassane Saley , Abderrahim El Mouhafid , Ahmed Jellal\",\"doi\":\"10.1016/j.physe.2024.116077\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>By studying the impact of a perpendicular magnetic field <span><math><mi>B</mi></math></span> on AB-bilayer graphene (AB-BLG) under dual gating, we yield several key findings for the ballistic transport of gate <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span>. Firstly, we discover that the presence of <span><math><mi>B</mi></math></span> leads to a decrease in transmission. At a high value of <span><math><mi>B</mi></math></span>, we notice the occurrence of anti-Klein tunneling over a significant area. Secondly, in contrast to the results reported in the literature, where high peaks were found with an increasing in-plane pseudomagnetic field applied to AB-BLG, we find a decrease in conductivity as <span><math><mi>B</mi></math></span> increases. However, it is worth noting that in both cases, the number of oscillations decreases compared to the result in the study where no magnetic field was present <span><math><mrow><mo>(</mo><mi>B</mi><mo>=</mo><mn>0</mn><mo>)</mo></mrow></math></span>. Thirdly, at the neutrality point, we demonstrate that the conductivity decreases and eventually reaches zero for a high value of <span><math><mi>B</mi></math></span>, which contrasts with the result that the conductivity remains unchanged regardless of the value taken by the in-plane field. Finally, we consider the diffusive transport with gate <span><math><mrow><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>2</mn><msub><mrow><mi>γ</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> and observe two scenarios. The amplitude of conductivity oscillations increases with <span><math><mi>B</mi></math></span> for energy <span><math><mi>E</mi></math></span> less than <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> but decreases in the opposite case <span><math><mrow><mi>E</mi><mo>></mo><msub><mrow><mi>U</mi></mrow><mrow><mi>∞</mi></mrow></msub></mrow></math></span>.</p></div>\",\"PeriodicalId\":20181,\"journal\":{\"name\":\"Physica E-low-dimensional Systems & Nanostructures\",\"volume\":\"165 \",\"pages\":\"Article 116077\"},\"PeriodicalIF\":2.9000,\"publicationDate\":\"2024-08-19\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physica E-low-dimensional Systems & Nanostructures\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1386947724001814\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"NANOSCIENCE & NANOTECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physica E-low-dimensional Systems & Nanostructures","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1386947724001814","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"NANOSCIENCE & NANOTECHNOLOGY","Score":null,"Total":0}
引用次数: 0
摘要
通过研究垂直磁场 B 对双闸流下 AB 双层石墨烯(AB-BLG)的影响,我们得出了闸流 U∞ 弹道传输的几个关键发现。首先,我们发现 B 的存在会导致传输率下降。当 B 值较高时,我们注意到在相当大的区域内出现了反克莱因隧道现象。其次,与文献报道的结果不同,我们发现随着 B 的增大,AB-BLG 的电导率会降低,而随着施加在 AB-BLG 上的面内伪磁场的增大,峰值会增大。不过,值得注意的是,与没有磁场(B=0)的研究结果相比,这两种情况下的振荡次数都有所减少。第三,在中性点,我们证明了当 B 值较高时,电导率会下降并最终趋于零,这与无论平面内磁场取值多少,电导率都保持不变的结果形成了鲜明对比。最后,我们考虑了栅极 U∞=0.2γ1 的扩散传输,观察到两种情况。当能量 E 小于 U∞ 时,电导振荡的振幅随 B 的增大而增大,但在相反的情况下,E>U∞ 则会减小。
Effect of a perpendicular magnetic field on bilayer graphene under dual gating
By studying the impact of a perpendicular magnetic field on AB-bilayer graphene (AB-BLG) under dual gating, we yield several key findings for the ballistic transport of gate . Firstly, we discover that the presence of leads to a decrease in transmission. At a high value of , we notice the occurrence of anti-Klein tunneling over a significant area. Secondly, in contrast to the results reported in the literature, where high peaks were found with an increasing in-plane pseudomagnetic field applied to AB-BLG, we find a decrease in conductivity as increases. However, it is worth noting that in both cases, the number of oscillations decreases compared to the result in the study where no magnetic field was present . Thirdly, at the neutrality point, we demonstrate that the conductivity decreases and eventually reaches zero for a high value of , which contrasts with the result that the conductivity remains unchanged regardless of the value taken by the in-plane field. Finally, we consider the diffusive transport with gate and observe two scenarios. The amplitude of conductivity oscillations increases with for energy less than but decreases in the opposite case .
期刊介绍:
Physica E: Low-dimensional systems and nanostructures contains papers and invited review articles on the fundamental and applied aspects of physics in low-dimensional electron systems, in semiconductor heterostructures, oxide interfaces, quantum wells and superlattices, quantum wires and dots, novel quantum states of matter such as topological insulators, and Weyl semimetals.
Both theoretical and experimental contributions are invited. Topics suitable for publication in this journal include spin related phenomena, optical and transport properties, many-body effects, integer and fractional quantum Hall effects, quantum spin Hall effect, single electron effects and devices, Majorana fermions, and other novel phenomena.
Keywords:
• topological insulators/superconductors, majorana fermions, Wyel semimetals;
• quantum and neuromorphic computing/quantum information physics and devices based on low dimensional systems;
• layered superconductivity, low dimensional systems with superconducting proximity effect;
• 2D materials such as transition metal dichalcogenides;
• oxide heterostructures including ZnO, SrTiO3 etc;
• carbon nanostructures (graphene, carbon nanotubes, diamond NV center, etc.)
• quantum wells and superlattices;
• quantum Hall effect, quantum spin Hall effect, quantum anomalous Hall effect;
• optical- and phonons-related phenomena;
• magnetic-semiconductor structures;
• charge/spin-, magnon-, skyrmion-, Cooper pair- and majorana fermion- transport and tunneling;
• ultra-fast nonlinear optical phenomena;
• novel devices and applications (such as high performance sensor, solar cell, etc);
• novel growth and fabrication techniques for nanostructures