Colossal magnetoresistance in doped manganites: A consequence of percolation and phase separation

Pradhan, A. K.; Feng, Y.; Roul, B. K.; Sahu, D. R.
July 2001
Applied Physics Letters;7/23/2001, Vol. 79 Issue 4
Academic Journal
We report measurements of the resistivity and magnetization of high-quality melt-processed La[sub 0.67]Ca[sub 0.33]MnO[sub 3] (LCM) and Sr-doped LCM materials that exhibit a sharp and enhanced metal–insulator transition (T[sub MI]) with significant colossal magnetoresistance (CMR) and two competing magnetic phases in the vicinity of T[sub MI]. Our results can well be explained using percolation in combination with the phase-separation scenario proposed for CMR. We propose that the spin polarization through grain boundaries and the enhanced grain connectivity between the ferromagnetic domains facilitate better percolation through a junction and filament-like resistor network. © 2001 American Institute of Physics.


Related Articles

  • Current localization and enhanced percolative low-field magnetoresistance in disordered half metals. Ju, Sheng; Cai, Tian-Yi; Li, Z. Y. // Applied Physics Letters;10/24/2005, Vol. 87 Issue 17, p172504 

    By modeling the magnetotransport in disordered half metals onto a random resistor network, we have performed numerical simulations on the low-field magnetoresistance (LFMR) and the current distribution in the network. It is found that there is a close relationship between the magnitude of LFMR...

  • Magnetoresistance of nanobridges of lanthanum–strontium manganite. Berezin, V. A.; Nikolaıchik, V. I.; Volkov, V. T.; Gorbatov, Yu. B.; Levashov, V. I.; Klimenko, G. L.; Tulin, V. A.; Matveev, V. N.; Khodos, I. I. // Technical Physics Letters;May99, Vol. 25 Issue 5, p398 

    Nanobridges are fabricated from lanthanum–strontium manganite deposited on Si[sub 3]N[sub 4] membranes perforated by a focused ion beam. The magnetoresistance is approx. 9% in fields of ∼1 kOe. Nonlinearity of the current–voltage characteristic of the bridges is observed, and...

  • Peculiar physical properties and the colossal magnetoresistance of manganites (Review). Loktev, V. M.; Loklev, V.M.; Pogorelov, Yu. G.; Pogorelov, Yu.G. // Low Temperature Physics;Mar2000, Vol. 26 Issue 3 

    An attempt is made to analyze the most important physical properties of manganites of the La-Ca-Mn-O type, which exhibit the colossal magnetoresistance effect. The primary focus is on the peculiarities of these compounds which are reflected in their crystalline, electronic, and magnetic...

  • Effect of oxygen content on magnetization and magnetoresistance properties of CMR manganites. Trukhanov, S. V.; Troyanchuk, I. O.; Korshunov, F. P.; Sirenko, V. A.; Szymczak, H.; Baerner, K. // Low Temperature Physics;Apr2001, Vol. 27 Issue 4, p283 

    The influence of oxygen content on the magnetization and electrical resistivity of Ln[sub 0.5]A[sub 0.5]MnO[sub 3] (Ln=La, Pr, Nd; A=Ca, Ba) manganites with the perovskite structure is investigated. It is shown that the La[sub 0.5]Ca[sub 0.5]MnO[sub 3-γ] compound undergoes a sequence of...

  • Giant volume magnetostriction in CMR manganites R[sub 1-x]Sr[sub x]MnO[sub 3](R=Sm, Nd). Abramovich, A. I.; Michurin, A. V. // Low Temperature Physics;Apr2001, Vol. 27 Issue 4, p278 

    Magnetization, ac initial magnetic susceptibility, resistance, magnetoresistance, thermal expansion and magnetostriction measurements are made on R[sub 1-x]Sr[sub x]MnO[sub 3] (R=Sm, x=0.33, 0.40, 0.45; R=Nd, x=0.33, 0.45) compounds. For all compounds in the T[sub C] region we observe a large...

  • Spin-lattice interaction in colossal magnetoresistance manganites. Lobad, Ahmed I.; Averitt, Richard D.; Kwon, Chuhee; Chuhee Kwon; Taylor, Antoinette J. // Applied Physics Letters;12/11/2000, Vol. 77 Issue 24 

    The metal-insulator transition and underlying spin dynamics in La[sub 0.7]D[sub 0.3]MnO[sub 3] (D=Ca, Sr) are investigated using optical pump-probe spectroscopy at 1.5 eV. Our measurements, which span the ferromagnetic-paramagnetic transition temperature, reveal that the dynamics of the...

  • Mo¨ssbauer spectroscopy and magnetoresistivity of [sup 57]Fe substituted Mn in La[sub 0.7-x]Y[sub x]Ca[sub 0.3]MnO[sub 3] manganites. Goya, G. F.; Souza, J. A.; Jardim, R. F. // Journal of Applied Physics;5/15/2002 Part 1, 2 & 3, Vol. 91 Issue 10, p7932 

    We have studied the general physical properties of polycrystalline samples of La[sub 0.7-x]Y[sub x]Ca[sub 0.3]Mn[sub 0.99][sup 57]Fe[sub 0.01]O[sub 3]; x = 0 and 0.1; manganites prepared through sol-gel precursors. Characterization of these samples through electrical resistivity, ρ(T), and...

  • Intrinsic spin valves in the layered manganite La[sub 1.4]Sr[sub 1.6]Mn[sub 2]O[sub 7]. Nachtrab, T.; Heim, S.; Mo¨ßle, M.; Kleiner, R.; Waldmann, O.; Koch, R.; Mu¨ller, P.; Kimura, T.; Tokura, Y. // Journal of Applied Physics;5/15/2002 Part 1, 2 & 3, Vol. 91 Issue 10, p7520 

    We report on transport measurements on micron-sized mesa structures fabricated on single crystals of the layered manganite La[sub 1.4]Sr[sub 1.6]Mn[sub 2]O[sub 7],probing the magnetoresistance of a single magnetic domain for current transport perpendicular to the layers. In magnetic fields...

  • Lattice effects and phase competition in charge ordered manganites. Rivadulla, F.; Hueso, L. E.; Migue´ns, D. R.; Sande, P.; Fondado, A.; Rivas, J.; Lo´pez-Quintela, M. A.; Ramos, C. A. // Journal of Applied Physics;5/15/2002 Part 1, 2 & 3, Vol. 91 Issue 10, p7412 

    A complete characterization of the magnetotransport and magnetoelastic properties of two classical examples of half doped manganites, Nd[sub 0.5]Sr[sub 0.5]MnO[sub 3] (NSMO) and La[sub 0.5]Ca[sub 0.5]MnO[sub 3] (LCMO), was carried out by electrical resistivity, magnetoresistance, thermoelectric...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics