This year's Nobel Prize has been conferred on two Russian-born British scientists, who made breakthrough in making single-atom thick 2D materials, namely, graphene. This graphene has been under intensive studies since their discovery. Some interesting facts are as follows:
(1)2D;
(2)made of carbon atoms;
(3)consisting of both planar sigma bonds, each of which containing a localized pair of covalent electrons that found the mechanical strength, and out-of-plane pi-bonds, which are extended and occupied by mobile electrons;
(4)the pi-bands have two complete Dirac cones, due to negligible spin-orbit coupling and various symmetries: inversion symmetry, time-reversal symmetry and 6-fold rotation symmetry. In the vicinity of these cones, the physics are governed by 2D Dirac equations.
(5)because of (4), highly conductive;
(6)Quantum Hall effect and Quantum Spin Hall effect have been predicted (and the former has been observed) in this material;
Not limited by this listing, it is guaranteed that in the future more new physics shall be exploited, such as the curvature effects and optical properties.
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