Magnetic properties of Chelyabinsk meteorite (15 February 2013) at high temperatures

Magnetic properties of the Chelyabinsk meteorite were studied in a wide temperature range - up to ∼ 1300 K. The analysis shows that the meteorite contains ferromagnetic inclusions of both Fe-Ni alloy and pure iron. It has visually been demonstrated that iron inclusions of the Chelyabinsk meteorite experience no β→γ structural phase transformation. © Published under licence by IOP Publishing Ltd.Russian Foundation for Basic Research, RFBR: 17-02-00005The research was carried out within the state assignment of Minobrnauki of Russia theme “Magnet” No.АААА-А18-118020290129-5, theme “Electron” No. АААА-А18-118020190098-5), theme “Spin” No. АААА-А18-118020290104-2 supported in part by RFBR (project No. 17-02-00005)

VO2: a two-fluid incoherent metal?

We present {\it ab initio} LDA+DMFT results for the many-particle density of states of $VO_{2}$ on the metallic side of the strongly first-order ($T$-driven) insulator-metal transition. In strong contrast to LDA predictions, there is {\it no} remnant of even correlated Fermi liquid behavior in the correlated metal. Excellent quantitative agreement with published photoemission and X-ray absorption experiments is found in the metallic phase. We argue that the absence of FL-quasiparticles provides a natural explanation for the bad-metallic transport for $T > 340 K$. Based on this agreement, we propose that the I-M transition in $VO_{2}$ is an orbital-selective Mott transition, and point out the relevance of orbital resolved one-electron and optical spectroscopy to resolve this outstanding issue.Comment: 4 pages, 3 figure