Abstract
The heavy fermion superconductor UPd2Al3, exhibits the relatively uncommon combination of an antiferromagnetic phase transition, at TN = 14.3 K, followed by a superconducting phase transition below 2 K without destruction of the ordered magnetic moment. Neutron inelastic scattering at low energy transfers in the vicinity of the antiferromagnetic ordering wave vector has been used to probe the magnetic fluctuation spectrum in the temperature range 130 mK < T < 20 K. In the normal antiferromagnetic phase the spectra may be characterized in terms of a damped spin wave interacting in a mean field manner with a quasielastic mode. By neutron polarization analysis the two modes have been shown to be polarized transverse to the sub-lattice magnetization vector. The spectra are used to estimate both the extrapolated low temperature linear term of the normal state heat capacity and the magnitude of TN. Satisfactory agreement with the measured values is obtained. In the superconducting state at the lowest temperatures evidence is presented for the opening of a gap at low energies which may suggest a connection between the antiferromagnetic fluctuations and superconductivity.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Steglich, F., Ahlheim, U., Bohm, A., Bredl, C.D., Caspary, R., Geibel, C., Grauel, A., Helfrich, R., Kohler, R., Lang, M., Mehner, A., Modler, R., Shank, C., Wassilew, C., Weber, G., Assmus, W., Sato, N. and Komatsubara, T. (1991) Phase Transitions in the Heavy Fermi Liquid State: CeCu2Si2, UNi2Al3 and UPd2Al3, Physica C185, 379–384.
Krimmel, A., Fischer, P., Roessli, B, Maletta, H., Geibel, C., Shank, C., Grauel, A., Loidl, A., Steglich, F. (1992) Neutron diffraction study of the heavy-fermion superconductors UM2Al3,(M = Pd, Ni), Z. Phys. 1186, 161–162.
Kita, H., Donni, A., Endoh, Y., Kakurai, K., Sato, N., Komatsubara, T.; (1994) Single crystal neutron diffraction study of the magnetic phase diagram of the Heavy Fermion Superconductor UPd2Al3), J. Phys. Soc. Japan. 63, 726–735.
Paolasini, L., Paixao, J.A., Lander, G.H., Burlet, P., Sato, N., Komatsubara, T.; (1994) Field dependence of magnetic structure of UPd2Al3 in the normal state, Phys. Rev. B49, 7072–7075.
Geibel, C., Shank, C., Thies, S., Kitazawa, H., Bredl, C.D., Bohm, A., Rau, M., Grauel, A., Caspary, R., Helfrich, R., Ahlheim, U., Weber, G., Steglich, F.; (1991) Heavy-Fermion superconductivity at Tc = 2K in the antiferromagnet Upd2Al3, Z. Phys. B84,1–2.
Steglich, F., Gegenwart, P., Geibel, C., Helfrich, R., Hellman, P., Lang, M., Link, A., Modler, R., Sparn, G., Buttgen, N., Loidl, A.; (1996) New observations concerning magnetism and superconductivity in the heavy-fermion metals, Physica B223, 1–8.
Krimmel, A., Loidl, A., Fisher, P., Roessli, B., Donni, A., Kita, H., Sato, N., Endoh, Y., Komatsubara, T., Geibel, C., Steglich, F. (1993) Single crystal neutron diffraction studies of the heavy fermion superconductor UPd2Al3, Solid State Comm. 87, 829–831.
Gaulin, B.D, Gibbs, D., Isaacs, E.D., Lussier, J.G., Reimers, J.N., Schroder, A., Taillefer, L., Zschack, P. (1994) Resonant magnetic x-ray scattering study of Phase transitions in UPd2Al3, Phys. Rev. Lett. 73, 890–893.
Petersen, T., Mason, T.E., Aeppli, G., Ramirez, A.P., Bucher, E., Kleiman, R.N.; (1994) Magnetic fluctuations and the superconducting transition in the heavy-fermion material UPd2Al3, Physica B199, 151–153.
Sato, N., Aso, N., Lander, G.H., Roessli, B., Komatsubara, T., Endoh, Y. (1997) Spin fluctuations in the Heavy Fermion Superconductor UPd2Al3 Studied by Neutron inelastic scattering, J. Phys. Soc. Japan. 66, 1884–1887.
Metoki, N., Haga, Y., Koike, Y., Aso, N., Onuki, Y. (1997) Coupling between Magnetic and Superconducting Order Parameters and Evidence for the spin excitation gap in superconducting state of a heavy fermion superconductor UPd2Al3, J Phys. Soc. Japan 66, 2560–2563.
Marshall, W. and Lovesey, S.W. (1971) Theory of Thermal Neutron Scattering, Oxford University Press, Oxford.
Bernhoeft, N. and Lonzarich, G.G. (1995) Scattering of slow neutrons from long wavelength magnetic fluctuations in UPt3, J. Phys. Condens. Matter 7, 7325–7333.
Bernhoeft, N. (1997) An Introduction to Magnetisation Density Fluctuations in Charged Fermi Liquids, Zuoz Summer School, (ed. A Furrer) ISSN 1019–6447, Villigen, Switzerland, p 73–87.
Sato, N., Sakon, T., Takeda, N., Komatsubara, T., Geibel, C., Steglich, F. (1992) Anisotropy in a Heavy Fermion Superconductor: UPd2Al3, J. Phys. Soc. Japan. 61, 32–34.
Sato, N., Inada, Y., Sakon, T., Imamura, K., Ishiguro, A., Kimura, J., Swada, A., Komatsubara, T.; (1994) Magnetic, Electrical and Thermal Properties of Heavy Fermion Superconductor UPd2Al3, IEEE Trans. Magn. 30, 1145–1147.
Lonzarich, G.G., Bemhoeft, N., McK Paul, D. (1989) Spin density fluctuations in magnetic metals, Physica 11156–157 699–705.
Bernhoeft N, Lonzarich GG, Mitchell PW, McK Paul D; (1983) Magnetic excitations in Ni,Al at low energies and long wavelengths, Phys. Rev. B28, 422–424.
Bernhoeft, N., Lonzarich, G.G., McK Paul, D., Mitchell, P.W.; (1986) Magnetic fluctuation spectra of very weak itinerant ferromagnets, Physica 136B, 443–446.
Bernhoeft, N., Hayden, S.M., Lonzarich, G.G., McK Paul, D., Lindley, E.J. (1989) Dispersive magnetic density fluctuations in Ni,Ga, Phys. Rev. Lett. 62, 657–660.
White, R.M. (1983) Quantum Theory of Magnetism, v.32 Solid State Sciences, Springer, Berlin.
Edwards, D.M. and Lonzarich, G.G. (1992) The entropy of fluctuating moments at low temperatures, Philosophical Magazine B65, 1185–1189.
Lonzarich, G.G. (1986) The magnetic equation of state and heat capacity in weak itinerant ferromagnets, J. Magn. Magn. Mat. 54, 612–616.
Moriya, T. and Takimoto, T. (1995) Anomalous Properties around Magnetic instabilities in heavy electron systems, J. Phys. Soc. Japan. 64, 960–969.
Solontsov, A. and Lacroix, C. (1997) Specfiç heat of soft-mode spin fluctuations in itinerant electron magnets, Physics Lett. A224, 298–302.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1998 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Bernhoeft, N. et al. (1998). UPd2Al3 : An Analysis of the Inelastic Neutron Scattering Spectra. In: Wagner, D., Brauneck, W., Solontsov, A. (eds) Itinerant Electron Magnetism: Fluctuation Effects. NATO Science Series, vol 55. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5080-4_4
Download citation
DOI: https://doi.org/10.1007/978-94-011-5080-4_4
Publisher Name: Springer, Dordrecht
Print ISBN: 978-0-7923-5203-7
Online ISBN: 978-94-011-5080-4
eBook Packages: Springer Book Archive