Phan, T.L and Nguyen, V.D and Ho, T.A and Nguyen, V. Khiem and Tran, D. Thanh and Nguyen, X. Phuc and Pham, Duc Thang and Yu, S.C. (2014) Inhomogeneous ferromagnetism and spin-glass-like behaviour in (Nd1-xYx)0.7Sr0.3MnO3 with x = 0.21 - 0.35. IEEE Transactions on Magnetics, 50 (6). p. 2502204. ISSN 0018-9464
Full text not available from this repository.Abstract
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, χ'(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, τ/τ0 ∝ (Tf /Tg - 1)-zv, where τ0 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 τ0 = 10-21-10-15s. These values are different from those expected for canonical SG systems with zv = 10 and τ0 = 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 τ0 and zv values toward those of canonical SG systems, which is ascribed to an expansi- n of SG clusters.
Item Type: | Article |
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Subjects: | Engineering Physics ISI-indexed journals |
Divisions: | Faculty of Engineering Physics and Nanotechnology (FEPN) |
Depositing User: | Ms. Cam Le Tran Thi |
Date Deposited: | 09 Nov 2015 05:46 |
Last Modified: | 09 Nov 2015 05:56 |
URI: | http://eprints.uet.vnu.edu.vn/eprints/id/eprint/1265 |
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