[Zurück]

T. Sakakibara, Y. Yamada, J. Custers, K. Yuno, T. Tayama, Y. Aoki, K. Machida:
"Nodal Structures of Heavy Fermion Superconductors Probed by the Specific-Heat Measurements in Magnetic Fields";
Journal of the Physical Society of Japan, 76 (2007), 5; S. 051004-1 - 051004-11.

Nodal Structures of Heavy Fermion Superconductors Probed by the Specific-Heat Measurements in Magnetic Fields

Toshiro Sakakibara, Atsushi Yamada, Jeroen Custers, Kazuhiro Yano, Takashi Tayama Hidekazu Aoki and Kazushige Machida

Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581
Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397
Department of Physics, Okayama University, Okayama 700-8530
Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria

(Received December 31, 2006; Accepted February 28, 2007; Published May 10, 2007)

Heavy electron superconductors mostly have anisotropic gap function which vanishes (has nodes) for certain directions in the momentum space. Since the nodal structure is closely related to the pairing mechanism, its experimental determination is very important. In anisotropic superconductors, low energy spectrum of the quasiparticles in the vortex state much depends on the nodal structure. In particular, the electronic specific heat has been demonstrated to exhibit the characteristic dependence on the angle between the field and the nodal direction, thereby the nodal structure can be probed experimentally. In this contribution, we present our recent experimental results on the field-orientation dependence of the specific heat on f electron superconductors CeRu₂, CeCoIn₅, PrOs₄Sb₁₂, and URu₂Si₂, and discuss their gap structures.

heavy fermion system, anisotropic superconductor, nodal structure, specific heat measurement, Doppler shift effect, quasiparticles, zero energy density of states

http://dx.doi.org/10.1143/JPSJ.76.051004

http://jpsj.ipap.jp/link?JPSJ/76/051004/