Phase Transition of La0.62Sr0.38MnO3 Perovskite Manganites
Bulk and nano La0.62Sr0.38MnO3 perovskite manganite samples were prepared using solid state and sonochemical reaction respectively. The ultrasonic velocities measurement was made on prepared samples using ultrasonic through transmission method, at a fundamental frequency of 5 MHz over wide range of temperatures. The temperature dependence of the ultrasonic parameters shows an interesting anomaly in bulk and nano perovskite samples. The observed dramatic softening and hardening in sound velocities are related to phase transitions. Further, a decrease in grain size in the nanostructured sample leads to a shift in the ferromagnetic transition temperature (TC) from 375 to 370 K.
G. Lalitha, D. Das, D. Bahadur and P. Venugopal Reddy, Elastic behavior of La0. 67Ca0.33MnO3: ZrO2 composites, J Alloy Compd. 464 (2008) 6-8.
W. J. Li, Bo Zhang and W. Lu, Structural properties and Raman spectroscopy of La (2+ 4x)/3Sr(1− 4x)/3Mn1− xCuxO3 (0⩽ x⩽ 0.2), Phys Lett A. 362 (2007) 327-330.
P.Sarkar, P. Mandal, A.K. Bera, S.M. Yusuf, L.S. Sharath Chandra and V. Ganesan, Field-induced first-order to second-order magnetic phase transition in Sm0.52Sr0.48MnO3, Phys. Rev. B. 78 (2008) 012415.
S. Sankarrajan, K. Sakthipandi and V. Rajendran, Temperature-dependent sound velocities, attenuation and elastic moduli anomalies in Pr1−xSrxMnO3 perovskite manganite materials at 0.28≤ X≤ 0.41, PHASE TRANSIT. 85 (2012) 427-443.
A. Urushibara, Y. Moritomo, T. Arima, A. Asamitsu, G. Kido and Y. Tokura, Insulator-metal transition and giant magnetoresistance in La1-xSrxMnO3, Phys. Rev. B, 51, (1995) 14103.
H.Y. Hwang, S.W. Cheong, P.G. Radaelli, M. Marezio and B. Batlog, Lattice Effects on the magnetoresistance in doped LaMnO3, Phy. Rev. Lett. 75 (1995) 914.
M. Lide, J. Rodriguez Martinez and J. Paul Attfield, Cation disorder and size effects in magnetoresistive manganese oxide perovskites, Phys. Rev.B, 54 (1996) R15622.
M. Uehara, S. Mori, C.H. Chen and S.W. Cheong, Percolative phase separation underlies colossal magnetoresistance in mixed-valant manganites, Nature, 399 (1999) 560-563.
M. Arunachalam, P. Thamilmaran, S. Sankarrajan, and K. Sakthipandi, Study of high temperature metal-insulator phase transition in La1−xCaxMnO3 employing in-situ ultrasonic studies, Physica B: Condensed Matter, 456 (2015) 118-124.
K. Sakthipandi and V. Rajendran, On-line phase transitions of bulk and nanocrystalline La1− xPbxMnO3 (x= 0.3, 0.4, and 0.5) perovskite manganite materials using ultrasonic measurements, Mater. Chem. Phys. 138 (2013) 581-592.
R.K. Zheng, C.F. Shu, J.Q. Xie, R.X. Huang and X.G. Li, Charge transport and ultrasonic properties in La0.57Ca0.43MnO3 perovskites, Mater. Chem. Phys. 75 (2002) 121-124.
Copyright (c) 2019 Sakthipandi K, Selvam M
This work is licensed under a Creative Commons Attribution 4.0 International License.
Views: Abstract : 152 | PDF : 95