Abstract
Temperature- and composition-control metal-insulator (M-I) transitions have been investigated for ordered double perovskites, $({\mathrm{Sr}}_{1\ensuremath{-}y}{\mathrm{Ca}}_{y}{)}_{2}{\mathrm{FeReO}}_{6}.$ ${\mathrm{Ca}}_{2}{\mathrm{FeReO}}_{6}$ $(y=1)$ shows the thermally induced M-I transition associated with the lattice-structural transition around 150 K. The alloyed system undergoes the M-I transition in the almost fully spin-polarized ground state around $y=0.4$ with minimal enhancement of the electronic specific-heat coefficient but with a large energy-scale $(\ensuremath{\sim}1 \mathrm{eV})$ change of the optical conductivity spectrum. These results indicate the importance of electron correlation, in particular the orbital correlation of Re ${t}_{2g}$ electrons, for the ferromagnetic M-I transition.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
