@Article{DíazGrAbRaChHe:2008:MaReXr,
               author = "D{\'{\i}}az, B. and Granado, E. and Abramof, Eduardo and Rappl, 
                         Paulo Henrique de Oliveira and Chitta, V. A. and Henriques, A. 
                         B.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and Instituto 
                         de F{\'{\i}}sica “Gleb Wataghin”, UNICAMP and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and Instituto de F{\'{\i}}sica, 
                         Universidade de S{\~a}o Paulo and Instituto de F{\'{\i}}sica, 
                         Universidade de S{\~a}o Paulo",
                title = "Magnetic resonant x-ray diffraction study of europium telluride",
              journal = "Physical Review B",
                 year = "2008",
               volume = "78",
               number = "134423",
                pages = "1--6",
             keywords = "difra{\c{c}}{\~a}o magn{\'e}tica de raios x ressonante, 
                         ordenamento magn{\'e}tico, telureto de eur{\'o}pio.",
             abstract = "Here we use magnetic resonant x-ray diffraction to study the 
                         magnetic order in a 1.5 m EuTe film grown on (111) BaF_2 by 
                         molecular-beam epitaxy. At Eu LII and LIII absorption edges, a 
                         resonant enhancement of more than two orders was observed for the 
                         sigma \→pi' diffracted intensity at half-order 
                         reciprocal-lattice points, consistent with the magnetic character 
                         of the scattering. We studied the evolution of the (1/2 1/2 1/2) 
                         magnetic reflection with temperature. When heating toward the Neel 
                         temperature (T_N), the integrated intensity decreased monotonously 
                         and showed no hysteresis upon cooling again, indicating a 
                         second-order phase transition. A power-law fit to the 
                         magnetization versus temperature curve yielded T_N=9.99(1) K and a 
                         critical exponent beta=0.36(1), which agrees with the 
                         renormalization theory results for three-dimensional Heisenberg 
                         magnets. The fits to the sublattice magnetization dependence with 
                         temperature, disregarding and considering fourth-order exchange 
                         interactions, evidenced the importance of the latter for a correct 
                         description of magnetism in EuTe. A value of 0.009 was found for 
                         the (2j_1+ j_2)/J_2 ratio between the Heisenberg J_2 and 
                         fourth-order j_1,2 exchange constants. The magnetization curve 
                         exhibited a round-shaped region just near T_N accompanied by an 
                         increase in the magnetic peak width, which was attributed to 
                         critical scattering above T_N. The comparison of the intensity 
                         ratio between the (1/2 1/2 1/2) and the (1 1/2 1 1/2 1 1/2) 
                         magnetic reflections proved that the Eu^2+ spins align within the 
                         (111) planes, and the azimuthal dependence of the (1/2 1/2 1/2) 
                         magnetic peak is consistent with the model of equally populated S 
                         domains.",
                  doi = "10.1103/PhysRevB.78.134423",
                  url = "http://dx.doi.org/10.1103/PhysRevB.78.134423",
                 issn = "1098-0121",
                label = "lattes: 0875527722518904 3 D{\'{\i}}azGrAbRaChHe:2008:MaReXr",
             language = "en",
           targetfile = "PhysRevB.78.134423.pdf",
        urlaccessdate = "27 abr. 2024"
}