Direct investigation of orbital ordering in a colossal magnetoresistance manganite by means of X-ray linear dichroism at the Mn L edge

Abstract

We have investigated for the first time the orbital ordering in a three-dimensional colossal magnetoresistance manganite, namely La7/8Sr1/8MnO3, by applying soft X-ray linear dichroism (XLD) to the Mn L edge. We found that the cooperative Jahn-Teller distorted orthorhombic phase, which is present at a temperature of 240 K, is probably accompanied by a predominantly cross type (x(2) - z(2))/(y(2) - z(2)) orbital ordering. This result is discussed in the light of different exchange interaction models.