Haga Yoshinori

Unconventional Heavy-Fermion Superconductivity of a New Transuranium Compound NpPd5Al2

We succeeded in growing a new transuranium compound NpPd 5 Al 2 with the tetragonal crystal structure by the Pb-flux method, and measured the electrical resistivity, specific heat, magnetic susceptibility and magnetization. NpPd 5 Al 2 is found to be a paramagnetic heavy-fermion superconductor with strong coupling Δ C /γ T c = 2.33 [ T c =4.9 K and γ= 200 mJ/(K 2 ·mol)]. The upper critical field H c2 at 0 K is large and highly anisotropic: H c2 (0) =37 kOe for H ∥[100] and H c2 (0) =143 kOe for H ∥[001]. H c2 is found to be strongly suppressed by the magnetic field, and the magnetization curve indicates a step-like increase at H c2 , which are due to the paramagnetic effect. The low-temperature electronic specific heat approximately follows the T 3 -dependence, indicating the existence of point nodes in the energy gap. The d -wave superconductivity with point nodes is most likely realized in this compound.

Strong-Coupling Superconductivity of CeIrSi3 with the Non-centrosymmetric Crystal Structure

We studied the pressure-induced superconductor CeIrSi

Magnetic and Superconducting Properties of CeTX3 (T: Transition Metal and X: Si and Ge) with Non-centrosymmetric Crystal Structure

_3

Evidence for Novel Pairing State in Noncentrosymmetric Superconductor CePt3Si: 29Si-NMR Knight Shift Study

with the non-centrosymmetric tetragonal structure under high pressure. The electrical resistivity and ac heat capacity were measured in the same run for the same sample. The critical pressure was determined to be

Heavy Fermions in YbAl 3 Studied by the de Haas-van Alphen Effect

P_{\rm c}

Magnetic Properties of Single Crystalline RCu2Si2 (R: Rare Earth)

= 2.25 GPa, where the antiferromagnetic state disappears. The heat capacity

Split Fermi Surface Properties of LaTGe3 (T: Transition Metal) and PrCoGe3 with the Non-centrosymmetric Crystal Structure

C_{\rm ac}

Pressure-Induced Superconductivity in Antiferromagnet CePd5Al2

shows both antiferromagnetic and superconducting transitions at pressures close to

Calorimetric Study in Single Crystalline RCu2Si2 (R: Rare Earth)

P_{\rm c}

27Al NMR Evidence for the Strong-Coupling d-Wave Superconductivity in NpPd5Al2

. On the other hand, the superconducting region is extended to high pressures of up to about 3.5 GPa, with the maximum transition temperature