TY  - JOUR
ID  - SisLab1265
UR  - Doi: 10.1109/TMAG.2014.2300852
IS  - 6
A1  - Phan, T.L
A1  - Nguyen, V.D
A1  - Ho, T.A
A1  - Nguyen, V. Khiem
A1  - Tran, D. Thanh
A1  - Nguyen, X. Phuc
A1  - Pham, Duc Thang
A1  - Yu, S.C.
Y1  - 2014///
N2  - The magnetic properties of polycrystalline ceramic samples (Nd1-xYx)0.7Sr0.3MnO3 with x = 0.21 - 0.35 were studied by means of dc magnetization and ac susceptibility measurements. Experimental results reveal a strong decrease of the ferromagnetic (FM)-paramagnetic phase-transition temperature (TC) from 97 to 65 K as increasing x from 0.21 to 0.35, respectively. There is magnetic inhomogeneity associated with short-range FM order. Particularly, the samples undergo a spin-glass (SG) phase transition at the so-called blocking temperature (TB) below TC, which shifts toward lower temperatures with increasing the applied field, Hex; TB ? Tg (the SG phase-transition temperature) as Hex ? 0. The existence of the SG behavior in these samples was also confirmed by frequency (f) dependences of the ac susceptibility. For the in-phase/real component, ?'(T), it shows a frequency-dependent peak at the SG freezing temperature (Tf); Tf ? Tg as f ? 0. Dynamics of this process were analyzed by means of the slowing down scaling law, ?/?0 ? (Tf /Tg - 1)-zv, where ?0 and zv are the characteristic time and critical exponent, respectively. Fitting the experimental Tf (f) data to the scaling law gave the results of zv = 10.1-12.3 and ?0 = 10-21-10-15s. These values are different from those expected for canonical SG systems with zv = 10 and ?0 = 10-13s, revealing the cluster-SG behavior of (Nd1-xYx)0.7Sr0.3MnO3 samples. Notably, the increase in Y content leads to the shift of ?0 and zv values toward those of canonical SG systems, which is ascribed to an expansi- n of SG clusters.
PB  - IEEE
JF  - IEEE Transactions on Magnetics
VL  - 50
SN  - 0018-9464
TI  - Inhomogeneous ferromagnetism and spin-glass-like behaviour in (Nd1-xYx)0.7Sr0.3MnO3 with x = 0.21 - 0.35
AV  - none
ER  -