Magnetic properties of “two electron” doped manganites: CaMn1−xWxO3

The magnetic properties as well as the electronic transport behaviors of Mn-site electron-doped manganites CaMn1−xWxO3  ( 0.05 ≤ x ≤ 0.20 ) have been studied. For low doping level ( x = 0.05 ) , the system shows the coexistence of multi-magnetic phases which is tunable by the applied magnetic field. For x = 0.07 , M – T curve shows an obvious phase transition believed to be from paramagnetism (PM) to G-antiferromagnetism (AFM) at around 190 K. With further increase of tungsten concentration ( x = 0.10 , 0.12 , 0.14 ) , besides a transition at T l ∼ 180 K, the system exhibits a peak at T h ∼ 350 K. According to the electron diffraction pattern, it is believed that the peak at T h is not a PM to charge ordering (CO) transition but a consequence of orbit ordering. The Jahn–Teller transition induced by the W doping should be responsible for the effect.