We report the experiment results and data analyses based on a polaron exchange model for La0.7Ca0.3MnO3 and Pr0.7(Sr1-xCax)0.3MnO3 epitaxial thin films. In the polaron exchange model with an energy balance condition, critical temperature of TC for stable ferromagnetic (FM) ordering should depend on 8710; E as kBTC =E0 exp(-ΔE/kBTC), where 8710; E denotes the potential barrier for the exchange polarons to overcome. Using the small polaron hopping model, the resistivity peak temperature TP is a function of the hopping energy Ehop. The dependence of TP on Ehop is similar to the dependence of TC on 8710; E, which reveals that the polaron exchange relates to FM and insulator--metal transitions. The result indicates that the polaron exchange model is a simple way for describing the FM ordering, and is very helpful for understanding of complex doped manganites.
We report the experiment results and data analyses based on a polaron exchange model for La0.7Ca0.3MnO3 and Pr0.7(Sr1-xCax)0.3MnO3 epitaxial thin films. In the polaron exchange model with an energy balance condition, critical temperature of TC for stable ferromagnetic (FM) ordering should depend on 8710; E as kBTC =E0 exp(-ΔE/kBTC), where 8710; E denotes the potential barrier for the exchange polarons to overcome. Using the small polaron hopping model, the resistivity peak temperature TP is a function of the hopping energy Ehop. The dependence of TP on Ehop is similar to the dependence of TC on 8710; E, which reveals that the polaron exchange relates to FM and insulator--metal transitions. The result indicates that the polaron exchange model is a simple way for describing the FM ordering, and is very helpful for understanding of complex doped manganites.
CHEN Li-Ping;MA Yu-Bin;SONG Xian-Feng;LIAN Gui-Jun;ZHANG Yan;XIONGGuang-Cheng. Relationship of Polaron Exchange with Ferromagnetic and Insulator--Metal Transitions in Doped Manganites[J]. 中国物理快报, 2008, 25(9): 3381-3384.
CHEN Li-Ping, MA Yu-Bin, SONG Xian-Feng, LIAN Gui-Jun, ZHANG Yan, XIONGGuang-Cheng. Relationship of Polaron Exchange with Ferromagnetic and Insulator--Metal Transitions in Doped Manganites. Chin. Phys. Lett., 2008, 25(9): 3381-3384.
[1] Millis A J, Littlewood P B and Shraiman B I 1995 Phys. Rev. Lett. 74 5144 [2] P Schiffer, P A Ramirez, W Bao and S W Cheong 1995 Phys. Rev. Lett. 75 3336 [3] Hwang H Y, Cheong S-W, Radaeli P G, Marezio M and BatloggB 1995 Phys. Rev. Lett. 75 914 [4] Roder H, Zang J and Bishop A R 1996 Phys. Rev. Lett. 76 1356 [5] Millis A J, Shraiman B I and Mueller R 1996 Phys.Rev. Lett. 77 175 [6] Zener C 1951 Phys. Rev. 82 403 [7] Anderson P W and Hasegawa H 1955 Phys. Rev. 100 675 [8] De Gennes P G 1960 Phys. Rev. 118 141 [9] Jaime M and Rubinstein M 1996 Phys. Rev. B 5411914 [10] Jaime M, Hardner H T, Salamon M B, Rubinstein M, Dorsey Pand Emin D 1997 Phys. Rev. Lett. 78 951 [11] De Teresa J M, Dorr K, Muller K H and Schultz L 1998 Phys. Rev. B 58 R5928 [12] Jakob G, Westerburg W, Martin F and Adrian H 1998 Phys. Rev. B 58 14966 [13] Fratini S and Ciuchi S 2003 Phys. Rev. Lett. 91 256403 [14] Mannella N, Rosenhahn A, Booth C H, Marchesini S, Mun BS, Yang S H, Ibrahim K, Tomioka Y and Fadley C S 2004 Phys.Rev. Lett. 92 166401 [15] Emin D and Holstein T 1969 Ann. Phys. (N.Y.) 53 439 [16] Song X F, Lian G J and Xiong G C 2005 Phys. Rev. B 71 214427 [17] Xiong G C, Ma Y B, Wang S Q, Song X F, Zhou X and Lian GJ 2006 Chin. Phys. Lett. 23 1273