Discovery of a Three-Dimensional Topological Dirac Semimetal, Na3Bi

@article{Liu2014DiscoveryOA,
  title={Discovery of a Three-Dimensional Topological Dirac Semimetal, Na3Bi},
  author={Z K Liu and B In Zhou and Y Zhang and Z. J. Wang and Hongming Weng and Dharmalingam Prabhakaran and S. K. Mo and Z. X. Shen and Zhong Fang and Xi Dai and Zahid Hussain and Y. L. Chen},
  journal={Science},
  year={2014},
  volume={343},
  pages={864 - 867}
}
A 3D Graphene? Discoveries of materials with exciting electronic properties have propelled condensed matter physics over the past decade. Two of the best-known examples, graphene and topological insulators, have something in common: a linear energy-momentum relationship—the Dirac dispersion—in their two-dimensional (2D) electronic states. Topological insulators also have a more mundane aspect of their electronic structure, characterized by a band gap. Another class of materials, topological… 
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Dimensional Crossover and Topological Phase Transition in Dirac Semimetal Na3Bi Films.
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Using angle-resolved photoemission spectroscopy, 3D Dirac cones associated with bulk electronic states near the Fermi level are observed in epitaxially grown α-Sn films on InSb(111), the first such TDS system realized in an elemental form.
Observation of Fermi arc surface states in a topological metal
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The systematic results collectively identify a topological phase in a gapless material and observe a pair of spin-polarized Fermi arc surface states on the surface of the Dirac semimetal Na3Bi at its native chemical potential.
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