Year: 2010
Type: article
Abstract: Precise band-filling control is performed on a strongly correlated electron system ${\text{Na}}_{x}{\text{CoO}}_{2}$, 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 ${\text{Na}}_{x}{\text{CoO}}_{2}$, differently from the conventional Lifshitz transition defined at $T=0$.
Source: Physical Review B
Authors: Yoshihiko Okamoto, Atsushi Nishio, Zenji Hiroi
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2077381300