Two C-type antiferromagnets with different magnetoresistive properties: Sm0.15Ca0.85MnO3 and Pr0.15Sr0.85MnO3

Inhomogeneous magnetism in La-dopedCaMnO3.I. Mesoscopic phase separation due to lattice-coupled ferromagnetic interactions

“…3,4,5,6,7 The application of simple DE across the whole of the phase diagram, however, contradicts experimental evidence by predicting either homogenous canting or the pure FM state at all points, in contrast with the rich phase diagram experimentally observed.…”

Crystal and magnetic structure of theLa1−xCaxMnOPissas1, Kallias2, Hofmann3 et al. 2002Phys. Rev. B561221View full textAdd to dashboardCite

“…The same type of monoclinic distortion has been observed in Sm 0.15 Ca 0.85 MnO 3 and Bi 0.15 Ca 0.85 MnO 3 compounds. 34,35 Due to the low x-ray scattering factor of oxygen the experiments done by Zheng et al 36 were not sensitive enough to find the correct structural transition in La 0.17 Ca 0.83 MnO 3 .…”

Structural and magnetic phase transitions in Pr0.15Sr0.85MnO3 at high pressure

“…On cooling, appearance of magnetic peaks located at d hkl  3.15 and 5.32 Å was observed below Neel temperature, T N  260 K at P = 0 ( fig. 4), evidencing the formation of the C-type AFM state [7,19]. At ambient pressure, the onset of long range magnetic order is accompanied by the structural transformation from the cubic Pm 3 m to the tetragonal I4/mcm phase with marked lattice elongation, while at P > 2.2 GPa the lattice distortion occurs within the tetragonal phase of I4/mcm symmetry.…”

“…The corresponding tetragonal distortion parameter is close to unity, t = l Mn-O1 /l Mn-O2  0.989 at P = 2.2 GPa. The onset of the antiferromagnetic long range order is followed by noticeable elongation of MnO 6 octahedra, the t value increases up to 1.022 at P = 2.2 GPa and T = 16 K. Such structural distortion is a result of the d(3z 2 -r 2 ) e g orbital polarization, characteristic for the C-type AFM ground state [19]. With an increase of pressure at T = 16 K ( fig.…”

“…In the C-type AFM structure manganese moments form ferromagnetic chains along the tetragonal c-axis with antiferromagnetic coupling between neighboring chains [7,19] Table 1. At P = 0 the results agree well with previous investigations [19].…”