Effect Of Tm Substitution On The Magnetic And Magnetocaloric Properties In The Intermetallic Compounds (tb1-xtmx)co2

The magnetic and magnetocaloric properties of the intermetallic compounds Tb1-xTmxCo2 (with x ≤ 0, 0.2 and 0.5) have been studied. It is found that partial replacement of Tb by Tm in TbCo 2 leads to a reduction in the ordering temperature, which is attributed to the decrease in the exchange strength due to the lower spin value of Tm3+ as compared with that of Tb3+. The analysis of the zero-field heat capacity data at low temperature shows that the coefficient of electronic heat capacity increases with increase in Tm content and is attributed to the presence of local spin fluctuations. The variation of the magnetocaloric effect (MCE) has been explained on the basis of the magnetic properties. Temperature dependence of the MCE shows that this system may be useful for magnetic refrigeration applications in a sub-room temperature regime. © 2007 IOP Publishing Ltd.40616201625Tishin, A.M., Spichkin, Y.I., (2003) The Magnetocaloric Effect and Its ApplicationsGschneidner, K.A., Pecharsky, V.K., Tsokol, A.O., (2005) Rep. Prog. Phys., 68 (6), p. 1479Pecharsky, V.K., Gschneidner, K.A., (1997) Appl. Phys. Lett., 70 (24), p. 3299Singh Niraj, K., Agarwal, S., Suresh, K.G., Nirmala, R., Nigam, A.K., Malik, S.K., (2005) Phys. Rev., 72, p. 014452Pecharsky, V.K., Gschneidner, K.A., (1999) J. Magn. Magn. Mater., 200 (1-3), p. 44Duc, N.H., Anh, T.K.D., Brommer, P.E., (2002) Physica, 319 (1-4), p. 1Singh Niraj, K., Suresh, K.G., Nigam, A.K., (2003) Solid State Commun., 127 (5), p. 373Khmelevskyi, S., Mohn, P., (2000) J. Phys.: Condens. Matter, 12 (45), p. 9453Bloch, D., Ewards, D.M., Shimizu, M., Voiron, J., (1975) J. Phys. F.: Met. Phys., 5 (6), p. 1217Inoue, J., Shimizu, M., (1982) J. Phys. F.: Met. Phys., 12 (8), p. 1811Singh Niraj, K., Kumar, P., Suresh, K.G., Nigam, A.K., Coelho, A.A., Gama, S., (2007) J. Phys.: Condens. Matter, 19 (3), p. 036213Duc, N.H., Hien, T.D., Brommer, P.E., Franse, J.J.M., (1992) J. Magn. Magn. Mater., 104-107, p. 1252Duc, N.H., Brommer, P.E., (1999) Handbook of Magnetic Materials, 12, p. 259Gopal, E.S.R., (1966) Specific Heats at Low TemperaturesBaranov, N.V., Yermakov, A.A., Pirogov, A.N., Proshkin, A.V., Gvasaliya, S.N., Podlesnyak, A., (2006) Phys. Rev., 73 (10), p. 104445Baranov, N.V., Bartashevich, M.I., Goto, T., Yermakov, A.A., Karkin, A.E., Pirogov, A.N., Teplykh, A.E., (1997) J. Alloys Compounds, 252 (1-2), p. 32Baranov, N.V., Yermakov, A.A., Pirogov, A.N., Teplykh, A.E., Inoue, K., Yu, H., (1999) Physica, 269 (3-4), p. 284Han, Z., Hua, Z., Wang, D., Zhang, C., Gu, B., Du, Y., (2006) J. Magn. Magn. Mater., 302 (1), p. 10