Charge ordering phase submerged in ferromagnetic ordering phase in the Nd_0.5Sr_0.5MnO₃ system

¹  National High Magnetic Field Laboratory, University of Science and Technology of China - Hefei 230026, PRC
²  Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China Hefei 230026, PRC

Corresponding author: pili@ustc.edu.cn

Received: 8 August 2007
Accepted: 4 September 2007

Abstract

In this letter, Nd_0.5Sr_0.5MnGa_xO₃ (0.0 x 0.075) manganites have been investigated. Diffuse satellite spots and streaks can be seen in transmission electron microscopy and the antiferromagnetic signal in electron spin resonance also occur early at 235 K which is much higher than the usually defined of the Nd_0.5Sr_0.5MnGa_xO₃ sample, indicating that the charge ordering phase already appears in the ferromagnetic regions ( = 250 K). This charge ordering phase is submerged by the ferromagnetic phase so that it is invisible in routine measurements. As the moves to lower temperature with Ga doping, the charge ordering phase exhibits itself gradually around 240 K.