Kapusta C, Riedi PC, Sikora M, Ibarra MR
Department of Solid State Physics, Faculty of Physics and Nuclear Techniques, University of Mining and Metallurgy, 30-059 Cracow, Poland and and Department of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife, KY16 9SS, Scotlan.
Phys Rev Lett. 2000 May 1;84(18):4216-9. doi: 10.1103/PhysRevLett.84.4216.
A 55Mn and 139La NMR study of La0.35Ca0.65MnO3 is reported. The zero field 55Mn spectra consist of two lines centered at 290 and 375 MHz. Their behavior under an applied magnetic field makes it possible to attribute them to regions of antiferromagnetically and ferromagnetically coupled Mn spins, respectively. This gives evidence for the existence of electronic phase segregation of microscopic ferromagnetic regions of double exchange coupled Mn spins over a charge ordered antiferromagnetic background. The behavior of these ferromagnetic regions in the applied magnetic field is related to the magnetoresistive properties of the manganites.
报道了对La0.35Ca0.65MnO3的55Mn和139La核磁共振研究。零场55Mn谱由两条分别以290和375 MHz为中心的谱线组成。它们在施加磁场下的行为使得可以分别将它们归因于反铁磁和铁磁耦合的Mn自旋区域。这为双交换耦合的Mn自旋的微观铁磁区域在电荷有序反铁磁背景上的电子相分离的存在提供了证据。这些铁磁区域在施加磁场中的行为与锰氧化物的磁电阻特性有关。
