Evolution of the CE-phase in layered manganites

Songxue Chi, University of Tennessee

Recent study of the hole-doped manganites has been centered on the coexistence and interplay of various magnetic and electronic phases, which is believed to be responsible for the colossal magnetoresistance (CMR). Of particular importance is the insulating CE-phase, a collaborated charge/orbital/spins-ordered state that neighbors almost all other ordered phases in the doping-bandwidth phase diagram. The CE phase stabilizes at half doping (x=0.5) of perovskite manganites of relatively small band width. As hole density deviates from the half-doping, there is an asymmetry between the under- (x<0.5) and over-doped (x>0.5) systems in charge/orbital order (CO/OO) as well as in magnetic orders. Studying how CE-phase evolves with hole-doping is a key to understand the origin of the complex states of manganites. In this talk our recent study of the static and dynamic magnetism in single-layered Pr1-xCa1+xMnO4 using neutron scattering technique will be represented. The magnetic structure of the half-doped system, the coexistence of commensurate and incommensurate magnetic orders in the underdoped region, and the origin of this coexistence will be discussed.

Back to Seminar Home Page

Last modified 15-July-2008 by website owner: NCNR (attn: )