{"title":"存在费米速度调制的狄拉克费米子边界态","authors":"Ullah Kalim, Jun-Tong Ren, Sha-Sha Ke, Yuan Feng, Hai-Feng Lü","doi":"10.1209/0295-5075/ad129f","DOIUrl":null,"url":null,"abstract":"<jats:title>Abstract</jats:title> We investigate the effect of a position-dependent Fermi velocity on the electronic properties of two-dimensional Dirac materials. A physical Fermi velocity distribution, which approaches a finite value at infinity and experiences a modulation near <jats:italic>x</jats:italic> = 0, is considered. Such a position-dependent Fermi velocity could be realized in the curved graphene or by applying strain. It is shown that the bound states are absent in the presence of a pure Fermi velocity modulation without an electrostatic potential well. However, an extra electrostatic potential modulation could produce the bound states. A set of discrete energy level spectrum and the corresponding wave functions are obtained by solving the Dirac equation exactly. Local probes such as scanning tunnel microscopy should be able to observe the predicted bound states in two-dimensional materials.","PeriodicalId":11738,"journal":{"name":"EPL","volume":"23 1","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Bound states of Dirac fermions in the presence of a Fermi velocity modulation\",\"authors\":\"Ullah Kalim, Jun-Tong Ren, Sha-Sha Ke, Yuan Feng, Hai-Feng Lü\",\"doi\":\"10.1209/0295-5075/ad129f\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<jats:title>Abstract</jats:title> We investigate the effect of a position-dependent Fermi velocity on the electronic properties of two-dimensional Dirac materials. A physical Fermi velocity distribution, which approaches a finite value at infinity and experiences a modulation near <jats:italic>x</jats:italic> = 0, is considered. Such a position-dependent Fermi velocity could be realized in the curved graphene or by applying strain. It is shown that the bound states are absent in the presence of a pure Fermi velocity modulation without an electrostatic potential well. However, an extra electrostatic potential modulation could produce the bound states. A set of discrete energy level spectrum and the corresponding wave functions are obtained by solving the Dirac equation exactly. Local probes such as scanning tunnel microscopy should be able to observe the predicted bound states in two-dimensional materials.\",\"PeriodicalId\":11738,\"journal\":{\"name\":\"EPL\",\"volume\":\"23 1\",\"pages\":\"\"},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2023-12-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"EPL\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1209/0295-5075/ad129f\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PHYSICS, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"EPL","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1209/0295-5075/ad129f","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
摘要 我们研究了随位置变化的费米速度对二维狄拉克材料电子特性的影响。我们考虑了费米速度的物理分布,它在无穷远处接近有限值,并在 x = 0 附近经历调制。这种随位置变化的费米速度可以在弯曲的石墨烯中或通过施加应变来实现。研究表明,在没有静电势阱的纯费米速度调制情况下,束缚态是不存在的。然而,额外的静电势调制可以产生束缚态。通过精确求解狄拉克方程,可以得到一组离散能级谱和相应的波函数。扫描隧道显微镜等局部探针应该能够在二维材料中观察到预测的束缚态。
Bound states of Dirac fermions in the presence of a Fermi velocity modulation
Abstract We investigate the effect of a position-dependent Fermi velocity on the electronic properties of two-dimensional Dirac materials. A physical Fermi velocity distribution, which approaches a finite value at infinity and experiences a modulation near x = 0, is considered. Such a position-dependent Fermi velocity could be realized in the curved graphene or by applying strain. It is shown that the bound states are absent in the presence of a pure Fermi velocity modulation without an electrostatic potential well. However, an extra electrostatic potential modulation could produce the bound states. A set of discrete energy level spectrum and the corresponding wave functions are obtained by solving the Dirac equation exactly. Local probes such as scanning tunnel microscopy should be able to observe the predicted bound states in two-dimensional materials.
期刊介绍:
General physics – physics of elementary particles and fields – nuclear physics – atomic, molecular and optical physics – classical areas of phenomenology – physics of gases, plasmas and electrical discharges – condensed matter – cross-disciplinary physics and related areas of science and technology.
Letters submitted to EPL should contain new results, ideas, concepts, experimental methods, theoretical treatments, including those with application potential and be of broad interest and importance to one or several sections of the physics community. The presentation should satisfy the specialist, yet remain understandable to the researchers in other fields through a suitable, clearly written introduction and conclusion (if appropriate).
EPL also publishes Comments on Letters previously published in the Journal.