Near fermi level electronic structure of Pr1-xSrxMnO3: Photoemission study

[摘要] In this study, we report the observation of a pseudogap associated with the insulator-metal transition in compositions of Pr1-xSrxMnO3 system with no charge ordering. Our valence-band photoemission study shows that the observed shifts in the near Fermi level density of states are abrupt at the Curie transition and occur over an energy scale of similar to 1 eV, strongly suggesting that the charge-ordering gap observed earlier in other manganites and the pseudogap observed here may indeed have the same origin. These results could be understood within the framework of models based on electronic phase separation where it has been shown that the pseudogap is a generic feature of the mixed-phase compositions. Also, our band-structure calculations on Pr0.75Sr0.25MnO3 show the possible existence of half metallicity in this system.

[发布日期] 2007-11-01

[关键词] TRANSITION;TRANSPORT