Role of double doping with C and RE2O3 oxides on the critical temperature and critical current of MgB2 phase

Authors

G Gajda, International Laboratory of HMF And LT
Andrzej Morawski, Institute of High Pressure Physics PAS
R Diduszko, Tele And Radio Research Institute, Poland
Tomasz Cetner, Institute of High Pressure Physics PAS
Md Shahriar Hossain, University of WollongongFollow
K Gruszka, Czestochowa University of Technology
Daniel Gajda, International Laboratory of HMF And LT
P Przyslupski, Polish Academy of Sciences

RIS ID

113298

Publication Details

Gajda, G., Morawski, A., Diduszko, R., Cetner, T., Hossain, M. A., Gruszka, K., Gajda, D. & Przyslupski, P. (2017). Role of double doping with C and RE₂O₃ oxides on the critical temperature and critical current of MgB₂ phase. Journal of Alloys and Compounds, 709 473-480.

Abstract

A series of MgB2 samples doped with C, RE2O3 oxides (RE = Ce, Nd), and C and RE2O3oxides was prepared by the hot isostatic pressing method at high pressure: 1 GPa under argon gas. Based on X-ray diffraction and magnetization measurements it was found that the RE2O3 is not incorporated into MgB2. A secondary REB4 phase is present after the synthesis. No decrease in the critical temperature (Tc) is observed after the RE2O3 doping. The Tc of C and RE2O3 doped MgB2 is decreased by 3 K. The doping decreases the diamagnetic response in comparison to pure MgB2 phase. The highest critical current density (Jc) was 3.4 x 105 A/cm2 at 4.2 K and 0.5 T for the bulk material, and the irreversibility field for the Nd2O3 doped sample was located at high field at T = 30 K. The results indicate that inside grains of pinning centers increase Jc from 4.2 K to 25 K and decrease Jc at 30 K. On the other hand, pinning centers between grains (precipitate) increase Jc at 30 K and decrease Jc from 4.2 K to 25 K in the middle and high magnetic fields. Our research shows that carbon-encapsulated boron creates a point pinning centers.