Discontinuous Lifshitz transition achieved by band-filling control in NaxCoO2

作者:Okamoto Yoshihiko*; Nishio Atsushi; Hiroi Zenji
来源:Physical Review B, 2010, 81(12): 121102.
DOI:10.1103/PhysRevB.81.121102

摘要

Precise band-filling control is performed on a strongly correlated electron system NaxCoO2, by changing the Na content, and the influence of this on the magnetic and thermodynamic properties is studied. It has been discovered that a phase boundary between a Pauli paramagnetic metal appearing at small x and a Curie-Weiss metal at large x is located within an extremely narrow range of 0.620 < x < 0.621. The transition between these is a Lifshitz transition of the pocket-vanishing type, exceptionally achieved by band-filling control. Abrupt changes in various properties across the boundary are remarkably observed, suggesting that the Lifshitz transition occurs discontinuously in NaxCoO2, differently from the conventional Lifshitz transition defined at T=0.

  • 出版日期2010-3