Transition From Kondo To Intermediate Valence Regime In (la1-xcex)ni: An Esr Study

We report on electron spin resonance (ESR) results for the series of compounds (La1-xCex)Ni doped with Gd. We show that from the Gd g-value and linewidth one can determine the concentration xc where the system goes from Kondo single impurity to Kondo lattice (and intermediate valence) regimes. The observed behaviour in both the g-value and the slope of the linewidth-T curves is explained using the indirect interaction between Gd and Ce moments. The calculation leads to the determination of the Ce-Gd exchange parameter JCe-Gd = 4.8 meV and the Ce-conduction electron exchange parameter \Jf-s\ = 19 meV, for x = 1.104397639768(1995) SCES'94 Proc. Int. Conf. Strongly Correlated Electron Systems, Physica B, 206-207(1996) SCES'96 Proc. Int. Conf. Strongly Correlated Electron Systems, Physica B, 223-224Brandt, N.B., Moshchalkov, V.V., (1984) Adv. Phys., 33, p. 373Medina, A.N., Hayashi, M.A., Cardoso, L.P., Gama, S., Gandra, F.G., (1998) Phys. Rev. B, 57, p. 5000Isikawa, Y., Mori, K., Fujii, A., Sato, K., (1986) J. Phys. Soc. Japan, 55, p. 3165Isikawa, Y., Mori, K., Mizushima, T., Fujii, A., Takeda, H., Sato, K., (1987) J. Magn. Magn. Mater., 70, p. 385Sato, K., Umohara, I., Isikawa, Y., Mori, K., Takeda, H., (1993) J. Appl. Phys., 73, p. 6623Gignoux, D., Givord, F., Lemaire, R., (1983) J. Less Common Met., 94, p. 165Barnes, S.E., (1981) Adv. Phys., 30, p. 801Gandra, F.G., Pontes, M.J., Schultz, S., Oseroff, S.B., (1987) Solid State Commun., 64, p. 859Gandra, F.G., Schultz, S., Oseroff, S.B., Fisk, Z., Smith, J.L., (1985) Phys. Rev. Lett., 55, p. 2719Krivenko, S.A., Zenin, A.G., Khaliullin, G.G., (1991) Sov. Phys.-JETP, 73, p. 576Elschner, B., Scholtt, M., (1988) J. Magn. Magn. Mater., 76-77, p. 444Al'tshuler, T.S., Kataev, V.E., Khaliullin, G.G., (1983) Sov. Phys.-Solid State, 25, p. 1239Gignoux, D., Gomez-Sal, J.C., (1984) Phys. Rev. B, 30, p. 3967Fillion, G., Gignoux, D., Givord, F., Lemaire, R., (1984) J. Magn. Magn. Mater., 44, p. 173Garcia Soldevilla, J., Gómez Sal, J.C., Rodríguez Fernández, J., Espeso, J.I., Monconduit, L., Allemand, J., Paccard, D., (1997) Physica B, 230-232, p. 117Dyson, F.J., (1955) Phys. Rev., 98, p. 349Kwapulinska, E., Kaczmarska, K., (1990) J. Magn. Magn. Mater., 88, p. 51Jaccarino, V., (1961) J. Appl. Phys. Suppl., 32, p. 102Rettori, C., Oseroff, S., Rao, D., Pagliuso, P., Barberis, G., Sarrao, J., Fisk, Z., Hundley, M., (1997) Phys. Rev. B, 55, p. 101