screening，kohnanomaly，friedeloscillation，andrkkyinteractioninbilayergraphene-外文文獻-資料下載頁
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【導(dǎo)讀】F. .We. DOI::,,sion[10],andRKKYinteraction[11].Inordertounder-. 2k. F. chiralnature,whereasinthe2DEG,the2k. F. backscattering. F. back-
【正文】 not converge], which means that intrinsicSLG is susceptible to ferromagic ordering in the presence of magic impurities [16,17] due to the divergentRKKY coupling.In doped (or gated) BLG, the oscillatory term in RKKYinteraction is restored due to the singularity of polarizability at q 188。 2kF, and the oscillating behavior dominates atlarge kFr. At large distances 2kFr C29 1, the dominantoscillating term in C5240。r222。 is given byC5240。r222。C24N0k2F2C25sin240。2kFr222。240。kFr222。2: (18)This is the same RKKY interaction as in a regular 2DEG,and it decreases as 1=r2, in contrast with 1=r3behavior inSLG [6].In conclusion, we calculate analytically the static wavevectordependent polarizability of bothundoped and dopedbilayer graphene within the RPA. For undoped BLG, wefind that screening is enhanced by a factor of log4 pared with ordinary 2D screening. The RKKY interactionin undoped BLG is zeroranged (C14 function). The dopedBLG screening function shows strongly enhanced Kohnanomaly at 2kFpared with the correspondingSLG and2DEG situations, which give rise to the usual RKKYinteraction and Friedel oscillation. We show that BLGscreening properties are qualitatively different from SLGscreening behavior in all wave vector regimes (q2kF,q2kF, and q 188。 2kF) with the BLG screening having astrong cusp at q 188。 2kF. Our theory applies only in thedensity regime (1010n5C21012cmC02), where theband dispersion is quadratic and only the lowest subbandis occupied [2], but the RPA should bewell valid due to theinteraction parameter rsbeing generally small in graphene[3]. There are obvious implications of our results for BLGcarrier transport limited byscreened Coulombscattering—in particular, the strong 2kFanomaly in screening will leadto strong temperature dependence in dc transport at low(T C28 TF) temperatures. This is in sharp contrast to SLGwhere 2kFbackscattering is suppressed.This work is supported by . ONR, NSFNRI, andSWAN.[1] For a recent review, for example, see Exploring Graphene:Recent Research Advances, A Special Issue of Solid StateCommunications, edited by S. Das Sarma, . Geim, P.Kim, and . MacDonald (Elsevier, New York, 2020),Vol. 143, and references therein.[2] E. McCann and . Fal’ko, Phys. Rev. Lett. 96, 086805(2020)。 J. Nilsson, . Castro Neto, . Peres, andF. Guinea, Phys. Rev. B 73, 214418 (2020)。 B. Partoensand . Peeters, Phys. Rev. B 74, 075404 (2020)。 M.Koshino and T. Ando, Phys. Rev. B 73, 245403 (2020)。 I.Snyman and . Beenakker, Phys. Rev. B 75, 045322(2020).[3] S. Morozov, K. Novoselov, M. Katsnelson, F. Schedin, D.Elias, J. Jaszczak, and A. Geim, Phys. Rev. Lett. 100,016602 (2020)。 K. Novoselov et al., Nature Phys. 2, 177(2020)。 J. Oostinga et al., Nature Mater. 7, 151 (2020).[4] . Hwang and S. Das Sarma, Phys. Rev. B 75, 205418(2020).[5] T. Ando, J. Phys. Soc. Jpn. 75, 074716 (2020).[6] B. Wunsch, T. Stauber, F. Sols, and F. Guinea, New J.Phys. 8, 318 (2020).[7] Y. Barlas et al., Phys. Rev. Lett. 98, 236601 (2020).[8] . Wang and T. Chakraborty, Phys. Rev. B 75, 041404(R) (2020).[9] . Hwang et al., Phys. Rev. Lett. 98, 186806 (2020)。 V.Cheianov and V. Fal’ko, Phys. Rev. Lett. 97, 226801(2020)。 K. Nomura and . MacDonald, Phys. Rev.Lett. 96, 256602 (2020)。 S. Adam et al., Proc. Natl.Acad. Sci. . 104, 18392 (2020).[10] W. Kohn, Phys. Rev. Lett. 2, 393 (1959)。 . Afnas’evand Yu. Kagan, Sov. Phys. JETP 16, 1030 (1963).[11] T. Ando, . Fowler, and F. Stern, Rev. Mod. Phys. 54,437 (1982).[12] S. Das Sarma and . Hwang, Phys. Rev. B 69, 195305(2020)。 Phys. Rev. Lett. 83, 164 (1999).[13] C. Bena, Phys. Rev. Lett. 100, 076601 (2020).[14] . Peierls, Quantum Theory of Solids (Clarendon Press,Oxford, 1995).[15] S. Das Sarma and Wuyan Lai, Phys. Rev. B 32, 1401(1985).[16] . Vozmediano, . LopezSancho, T. Stauber,and F. Guinea, Phys. Rev. B 72, 155121 (2020).[17] L. Brey, . Fertig, and S. Das Sarma, Phys. Rev. Lett.99, 116802 (2020).PRL 101, 156802 (2020)PHYSICAL REVIEW LETTERSweek ending10 OCTOBER 20201568024
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