Evidence for the band broadening across the ferromagnetic transition in Cr${}_{1/3}$NbSe${}_2$

Abstract

The electronic structure of Cr${}_{1/3}$NbSe${}_2$ is studied via optical spectroscopy. We observe two low-energy interband transitions in the paramagnetic phase, which split into four peaks as the compound enters the ferromagnetic state. The band structure calculation indicates the four peaks are interband transitions to the spin up Cr e${}_g$ states. We show that the peak splitting below the Curie temperature is \emph{not} due to the exchange splitting of spin up and down bands, but directly reflects a band broadening effect in Cr-derived states upon the spontaneous ferromagnetic ordering.

6 pages, 5 figures, to be published in Phys. Rev. B

References in corpus (3)

• The anomalous Hall Effect and magnetoresistance in the layered ferromagnet Fe_{1/4}TaS_2: the inelastic regime
• Optical study of the charge-density-wave mechanism in 2$H$-TaS${}_2$ and Na${}_x$TaS${}_2$
• Theoretical Evidence for the Berry-Phase Mechanism of Anomalous Hall Transport: First-principles Studies on CuCr${}_2$Se${}_{4-x}$Br${}_x$