狄拉克锥
狄拉克锥是一种特殊二维材料中的电子能带结构,在此结构中,电子具有像光一样的相对论性质。科研人员认为狄拉克锥可能是通向未来超级芯片、量子计算机、超导和桌面相对论技术的路径。[1][2][3][4]
典型的狄拉克锥材料包括石墨烯、拓扑绝缘体、铋锑薄膜和其他新型纳米材料。[1][5][6] 这些特殊二维材料中电子的能量和动量具有线性的色散关系,因此其费米能级附近的电子能带结构呈现出上下两个锥体,分别代表电子和空穴。两个锥体的顶端刚好相连,形成“零带隙”的半金属相.
狄拉克锥的名字来源于狄拉克方程,由保罗·狄拉克 (Paul Dirac) 提出,用以统一描述物质的量子力学效应和相对论效应。狄拉克锥可以是各向同性,也可是各向异性的。石墨烯中存在各向同性的狄拉克锥,由飞利浦·华莱士 (P. R. Wallace) 于1947提出[7],并由诺贝尔物理学奖得主安德烈·海姆 (Andre Geim) 和康斯坦丁·诺沃肖洛夫 (Konstantin Novoselov) 于2005年首次在实验中观察到。[8] 麻省理工学院的唐爽和崔瑟豪斯夫人(Mildred Dresselhaus)于2012年在其唐-崔瑟豪斯理论 (Tang-Dresselhaus Theory) 中首次提出了系统性构建各向异性狄拉克锥的方法。[9][10][11]
描述
在量子力学中,狄拉克锥描述 [12]价带和导带的能量在二维晶格k空间中,除了零维狄拉克点所在的位置外,其他任何动量的价带和导带能量都不相等。由于是锥型,电传导可以用无质量费米子的电荷载流子来描述,在理论上这种情况可由相对论性的狄拉克方程来处理。 [13]无质量费米子可以导致各种奇异的量子霍尔效应、或是拓扑材料中的磁电效应和超高载流子迁移率。 [14] [15]在 2008-2009 年实验上使用角分辨光电子能谱(ARPES) 对钾-石墨插层化合物KC 8 [16]和几种铋基合金的狄拉克锥进行了观察。[17] [18] [15]
狄拉克锥是二维材料 (像是单层石墨烯)或拓扑绝缘体的表面态的特征。狄拉克锥在材料中是线性色散关系,由能量与晶体动量的两个分量k x和k y来描述。然而,这个概念可以扩展到三维材料,其中狄拉克半金属由能量与k x 、 k y和k z的线性色散关系来定义。在动量空间中,色散关系为超圆锥体,它具有双重简并能带,也在狄拉克点相交。 [15]狄拉克半金属同时包含时间反演对称性和空间反演对称性;当其中一个对称性被破坏时,狄拉克点可以分裂成两个外尔点,材料变成外尔半金属。 [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] 在2014年,实验上利用ARPES对狄拉克半金属砷化镉 的能带结构进行了直接观测。 [30] [31] [32]
模拟系统
已在许多物理系统实现狄拉克点,例如等离子体学、声子学或纳米光子学(微腔、 [33]光子晶体[34] )。
参看
参考文献
- ^ 1.0 1.1 Novoselov, K.S.; Geim, A.K. The rise of graphene. Nature Materials. 2007, 6 (3): 183–191. doi:10.1038/nmat1849.
- ^ Hasan, M.Z.; Kane, C.L. Topological Insulators. Rev. Mod. Phys. 2010, 82 (4): 3045. doi:10.1103/revmodphys.82.3045.
- ^ Superconductors: Dirac cones come in pairs. Advanced Institute for Materials Research. wpi-aimr.tohoku.ac.jp. Research Highlights. Tohoku University. 29 Aug 2011 [2 Mar 2018].[失效链接]
- ^ Basic Research Needs for Microelectronics. (页面存档备份,存于互联网档案馆) US Department of Energy, Office of Science, October 23-25, 2018.
- ^ Dirac cones could exist in bismuth–antimony films (页面存档备份,存于互联网档案馆). Physics World, Institute of Physics, April 17, 2012.
- ^ Hsieh, David. A topological Dirac insulator in a quantum spin Hall phase. Nature. 2008, 452: 970–974. doi:10.1038/nature06843.
- ^ Wallace, P. R. The Band Theory of Graphite. Physical Review. 1947, 71 (9): 622–634. Bibcode:1947PhRv...71..622W. doi:10.1103/PhysRev.71.622.
- ^ The Nobel Prize in Physics 2010 Press Release (页面存档备份,存于互联网档案馆). Nobelprize.org, October 5, 2010. Retrieved 2011-12-31.
- ^ New material shares many of graphene’s unusual properties. Thin films of bismuth-antimony have potential for new semiconductor chips, thermoelectric devices (页面存档备份,存于互联网档案馆). MIT News Office (April 24, 2012).
- ^ Tang, Shuang; Dresselhaus, Mildred. Constructing Anisotropic Single-Dirac-Cones in BiSb Thin Films. Nano Letters. 2012, 12 (4): 2021–2026. doi:10.1021/nl300064d.
- ^ Tang, Shuang; Dresselhaus, Mildred. Constructing A Large Variety of Dirac-Cone Materials in the BiSb Thin Film System. Nanoscale. 2012, 4 (24): 7786–7790. doi:10.1039/C2NR32436A.
- ^ Fuchs, Jean-Noël; Lim, Lih-King; Montambaux, Gilles. Interband tunneling near the merging transition of Dirac cones (PDF). Physical Review A. 2012, 86 (6): 063613 [2023-01-21]. Bibcode:2012PhRvA..86f3613F. S2CID 67850936. arXiv:1210.3703 . doi:10.1103/PhysRevA.86.063613. (原始内容 (PDF)存档于2023-01-21).
- ^ Novoselov, K.S.; Geim, A.K.; Morozov, S.V.; Jiang, D.; Katsnelson, M.I.; Grigorieva, I.V.; et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature. 10 Nov 2005, 438 (7065): 197–200 [2 Mar 2018]. Bibcode:2005Natur.438..197N. PMID 16281030. S2CID 3470761. arXiv:cond-mat/0509330 . doi:10.1038/nature04233. (原始内容存档于2023-05-08).
- ^ Two-dimensional Dirac materials: Structure, properties, and rarity. Phys.org. [25 May 2016]. (原始内容存档于2023-01-21).
- ^ 15.0 15.1 15.2 Hasan, M.Z.; Moore, J.E. Three-dimensional topological insulators. Annual Review of Condensed Matter Physics. 2011, 2: 55–78. Bibcode:2011ARCMP...2...55H. S2CID 11516573. arXiv:1011.5462 . doi:10.1146/annurev-conmatphys-062910-140432 (英语).
- ^ Grüneis, A.; Attaccalite, C.; Rubio, A.; Vyalikh, D.V.; Molodtsov, S.L.; Fink, J.; et al. Angle-resolved photoemission study of the graphite intercalation compound KC8: A key to graphene. Physical Review B. 2009, 80 (7): 075431. Bibcode:2009PhRvB..80g5431G. doi:10.1103/PhysRevB.80.075431. hdl:10261/95912 .
- ^ Hsieh, D.; Qian, D.; Wray, L.; Xia, Y.; Hor, Y.S.; Cava, R.J.; Hasan, M.Z. A topological Dirac insulator in a quantum spin Hall phase. Nature. 2008, 452 (7190): 970–974. Bibcode:2008Natur.452..970H. ISSN 0028-0836. PMID 18432240. S2CID 4402113. arXiv:0902.1356 . doi:10.1038/nature06843 (英语).
- ^ Hsieh, D.; Xia, Y.; Qian, D.; Wray, L.; Dil, J.H.; Meier, F.; et al. A tunable, topological insulator in the spin helical Dirac transport regime. Nature. 2009, 460 (7259): 1101–1105. Bibcode:2009Natur.460.1101H. PMID 19620959. S2CID 4369601. arXiv:1001.1590 . doi:10.1038/nature08234.
- ^ Wehling, T.O.; Black-Schaffer, A.M.; Balatsky, A.V. Dirac materials. Advances in Physics. 2014, 63 (1): 1. Bibcode:2014AdPhy..63....1W. S2CID 118557449. arXiv:1405.5774 . doi:10.1080/00018732.2014.927109.
- ^ Singh, Bahadur; Sharma, Ashutosh; Lin, H.; Hasan, M.Z.; Prasad, R.; Bansil, A. Topological electronic structure and Weyl semimetal in the TlBiSe2 class. Physical Review B. 2012-09-18, 86 (11): 115208. S2CID 119109505. arXiv:1209.5896 . doi:10.1103/PhysRevB.86.115208.
- ^ Huang, S.-M.; Xu, S.-Y.; Belopolski, I.; Lee, C.-C.; Chang, G.; Wang, B.K.; et al. A Weyl Fermion semimetal with surface Fermi arcs in the transition metal monopnictide TaAs class. Nature Communications. 2015, 6: 7373. Bibcode:2015NatCo...6.7373H. PMC 4490374 . PMID 26067579. doi:10.1038/ncomms8373.
- ^ Weng, Hongming; Fang, Chen; Fang, Zhong; Bernevig, B. Andrei; Dai, Xi. Weyl semimetal phase in non-centrosymmetric transition-metal monophosphides. Physical Review X. 2015, 5 (1): 011029. Bibcode:2015PhRvX...5a1029W. S2CID 15298985. arXiv:1501.00060 . doi:10.1103/PhysRevX.5.011029.
- ^ Xu, S.-Y.; Belopolski, I.; Alidoust, N.; Neupane, M.; Bian, G.; Zhang, C.; et al. Discovery of a Weyl Fermion semimetal and topological Fermi arcs. Science. 2015, 349 (6248): 613–617 [2023-01-21]. Bibcode:2015Sci...349..613X. PMID 26184916. S2CID 206636457. arXiv:1502.03807 . doi:10.1126/science.aaa9297. (原始内容存档于2023-01-21).
- ^ Xu, Su-Yang; Alidoust, Nasser; Belopolski, Ilya; Yuan, Zhujun; Bian, Guang; Chang, Tay-Rong; et al. Discovery of a Weyl fermion state with Fermi arcs in niobium arsenide. Nature Physics. 2015, 11 (9): 748–754 [2023-01-21]. ISSN 1745-2481. S2CID 119118252. arXiv:1504.01350 . doi:10.1038/nphys3437. (原始内容存档于2023-01-13) (英语).
- ^ Huang, Xiaochun; Zhao, Lingxiao; Long, Yujia; Wang, Peipei; Chen, Dong; Yang, Zhanhai; et al. Observation of the chiral-anomaly-induced negative magnetoresistance in 3‑D Weyl semimetal TaAs. Physical Review X. 2015, 5 (3): 031023. Bibcode:2015PhRvX...5c1023H. S2CID 55929760. arXiv:1503.01304 . doi:10.1103/PhysRevX.5.031023.
- ^ Zhang, Cheng-Long; Xu, Su-Yang; Belopolski, Ilya; Yuan, Zhujun; Lin, Ziquan; Tong, Bingbing; et al. Signatures of the Adler–Bell–Jackiw chiral anomaly in a Weyl fermion semimetal. Nature Communications. 2016-02-25, 7 (1): 10735. ISSN 2041-1723. PMC 4773426 . PMID 26911701. doi:10.1038/ncomms10735 (英语).
- ^ Schoop, Leslie M.; Ali, Mazhar N.; Straßer, Carola; Topp, Andreas; Varykhalov, Andrei; Marchenko, Dmitry; et al. Dirac cone protected by non-symmorphic symmetry and three-dimensional Dirac line node in ZrSiS. Nature Communications. 2016, 7 (1): 11696. Bibcode:2016NatCo...711696S. ISSN 2041-1723. PMC 4895020 . PMID 27241624. arXiv:1509.00861 . doi:10.1038/ncomms11696.
- ^ Neupane, M.; Belopolski, I.; Hosen, Md.M.; Sanchez, D.S.; Sankar, R.; Szlawska, M.; et al. Observation of topological nodal fermion semimetal phase in ZrSiS. Physical Review B. 2016, 93 (20): 201104(R). ISSN 2469-9969. S2CID 118446447. arXiv:1604.00720 . doi:10.1103/PhysRevB.93.201104.
- ^ Lu, Ling; Fu, Liang; Joannopoulos, John D.; Soljačic, Marin. Weyl points and line nodes in gyroid photonic crystals (PDF). Nature Photonics. 17 Mar 2013, 7 (4): 294–299 [2 Mar 2018]. Bibcode:2013NaPho...7..294L. S2CID 5144108. arXiv:1207.0478 . doi:10.1038/nphoton.2013.42. (原始内容存档 (PDF)于2023-01-21).
- ^ Neupane, Madhab; Xu, Su-Yang; Sankar, Raman; Nasser, Alidoust; Bian, Guang; Liu, Chang; et al. Observation of a three-dimensional topological Dirac semimetal phase in high-mobility Cd3As2. Nature Communications. 2014, 5: 3786. Bibcode:2014NatCo...5.3786N. PMID 24807399. arXiv:1309.7892 . doi:10.1038/ncomms4786 .
- ^ Sankar, R.; Neupane, M.; Xu, S.-Y.; Butler, C.J.; Zeljkovic, I.; Panneer Muthuselvam, I.; et al. Large single crystal growth, transport property, and spectroscopic characterizations of three-dimensional Dirac semimetal Cd3As2. Scientific Reports. 2015, 5: 12966. Bibcode:2015NatSR...512966S. PMC 4642520 . PMID 26272041. doi:10.1038/srep12966.
- ^ Borisenko, Sergey; Gibson, Quinn; Evtushinsky, Danil; Zabolotnyy, Volodymyr; Büchner, Bernd; Cava, Robert J. Experimental realization of a three-dimensional Dirac semimetal. Physical Review Letters. 2014, 113 (2): 027603. Bibcode:2014PhRvL.113b7603B. ISSN 0031-9007. PMID 25062235. S2CID 19882802. arXiv:1309.7978 . doi:10.1103/PhysRevLett.113.027603.
- ^ Terças, H.; Flayac, H.; Solnyshkov, D. D.; Malpuech, G. Non-Abelian Gauge Fields in Photonic Cavities and Photonic Superfluids. Physical Review Letters. 2014-02-11, 112 (6): 066402. Bibcode:2014PhRvL.112f6402T. PMID 24580697. S2CID 10674352. arXiv:1303.4286 . doi:10.1103/PhysRevLett.112.066402.
- ^ He, Wen-Yu; Chan, C. T. The Emergence of Dirac points in Photonic Crystals with Mirror Symmetry. Scientific Reports. 2015-02-02, 5 (1): 8186. ISSN 2045-2322. PMC 4650825 . PMID 25640993. doi:10.1038/srep08186 (英语).