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arXiv · 1008.2703

Dirac Point Degenerate with Massive Bands at a Topological Quantum Critical Point

J. C. Smith·S. Banerjee·V. Pardo·W. E. Pickett
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Abstract

The quasi-linear bands in the topologically trivial skutterudite insulator CoSb$_3$ are studied under adiabatic, symmetry-conserving displacement of the Sb sublattice. In this cubic, time-reversal and inversion symmetric system, a transition from trivial insulator to topological point Fermi surface system occurs through a critical point in which massless (Dirac) bands are {\it degenerate} with massive bands. Spin-orbit coupling does not alter the character of the transition. The mineral skutterudite (CoSb$_3$) is very near the critical point in its natural state.

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J. C. Smith, S. Banerjee, V. Pardo, W. E. Pickett. 2010-08-16. Dirac Point Degenerate with Massive Bands at a Topological Quantum Critical Point. https://doi.org/10.1103/physrevlett.106.056401

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