doi:10.1103/PhysRevLett.125.256804engBrey, L.Stauber, T.Slipchenko, T.Martín-Moreno, L.Plasmonic Dirac Cone in Twisted Bilayer GrapheneART-2020-122323We discuss plasmons of biased twisted bilayer graphene when the Fermi level lies inside the gap. The collective excitations are a network of chiral edge plasmons (CEP) entirely composed of excitations in the topological electronic edge states that appear at the AB-BA interfaces. The CEP form a hexagonal network with a unique energy scale ?p=(e2)/(?0?t0) with t0 the moiré lattice constant and ? the dielectric constant. From the dielectric matrix we obtain the plasmon spectra that has two main characteristics: (i) a diverging density of states at zero energy, and (ii) the presence of a plasmonic Dirac cone at â., ?~?p/2 with sound velocity vD=0.0075c, which is formed by zigzag and armchair current oscillations. A network model reveals that the antisymmetry of the plasmon bands implies that CEP scatter at the hexagon vertices maximally in the deflected chiral outgoing directions, with a current ratio of 4/9 into each of the deflected directions and 1/9 into the forward one. We show that scanning near-field microscopy should be able to observe the predicted plasmonic Dirac cone and its broken symmetry phases.2020http://zaguan.unizar.es/record/9908310.1103/PhysRevLett.125.256804http://zaguan.unizar.es/record/99083oai:zaguan.unizar.es:99083info:eu-repo/grantAgreement/ES/DGA/Q-MADinfo:eu-repo/grantAgreement/EC/H2020/785219/EU/Graphene Flagship Core Project 2/GrapheneCore2This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 785219-GrapheneCore2info:eu-repo/grantAgreement/EC/H2020/881603/EU/Graphene Flagship Core Project 3/GrapheneCore3This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 881603-GrapheneCore3info:eu-repo/grantAgreement/ES/MINECO/FIS2017-82260-Pinfo:eu-repo/grantAgreement/ES/MINECO/MAT2017-88358-C3-1-Rinfo:eu-repo/grantAgreement/ES/MINECO/PGC2018-096955-B-C42info:eu-repo/grantAgreement/ES/MINECO/PGC2018-097018-B-100Physical Review Letters 125, 25 (2020), 256804 [6 pp]All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess