eprintid: 1797
rev_number: 9
eprint_status: archive
userid: 5
dir: disk0/00/00/17/97
datestamp: 2016-07-06 06:35:15
lastmod: 2017-06-15 01:55:53
status_changed: 2016-07-06 06:35:15
type: article
metadata_visibility: show
creators_name: T., A. Ho
creators_name: T., D. Thanh
creators_name: T., V. Manh
creators_name: T., O. Ho
creators_name: Pham, Duc Thang
creators_name: T., L. Phan
creators_name: S., C. Yu
creators_id: pdthang@vnu.edu.vn
title: Critical Behavior of La0.7Ca0.3MnO3 Nanoparticles
ispublished: pub
subjects: Phys
divisions: fac_physic
abstract: We used the modified Arrott plot method to analyze magnetic-field dependences of magnetization, M(H), around the ferromagneticparamagnetic
(FM-PM) phase-transition temperature (TC) of three nanocrystalline La0.7Ca0.3MnO3 samples with average crystallite sizes d = 40,
23, and 16 nm. The analyses obtained the values of critical parameters to be TC µ 261 K, ¢ = 0.485 « 0.005, £ = 1.051 « 0.094 and ¤ = 3.1 «
0.1 for the sample with d = 40 nm, TC µ 252 K, ¢ = 0.525 « 0.010, £ = 0.893 « 0.139 and ¤ = 2.7 « 0.1 for d = 23 nm, and TC µ 236 K,
¢ = 0.621 « 0.008, £ = 0.825 « 0.007 and ¤ = 2.2 « 0.2 for d = 16 nm. With these critical values, the M(H) data points around TC of the
samples fall into two universal branches of a scaling function M(H, ¾) = «¾«
¢f«(H/«¾«
¢+£
), with ¾ = (T ¹ TC)/TC, f+ for T > TC and f¹ for T < TC.
The results reveal that the crystallite-size reduction of nanoparticles decreases the TC value. This is ascribed to the decrease of FM doubleexchange
interactions between Mn3+ and Mn4+ ions, which is related to the ¢ change from 0.485 for d = 40 nm to 0.621 for d = 16 nm,
corresponding to the change in FM order from the long-range type to the short-range one.
date: 2015
date_type: published
official_url: doi:10.2320/matertrans.MA201552
full_text_status: none
publication: Materials Transactions
volume: 56
number: 9
pagerange: 1331-1334
refereed: TRUE
citation:   T., A. Ho and T., D. Thanh and T., V. Manh and T., O. Ho and Pham, Duc Thang and T., L. Phan and S., C. Yu  (2015) Critical Behavior of La0.7Ca0.3MnO3 Nanoparticles.  Materials Transactions, 56  (9).   pp. 1331-1334.