Pei-Chun Ho

Ferromagnetic ordering and simultaneous fast magnetization tunneling in a Ni4 single-molecule magnet.

Low-temperature heat capacity and oriented single-crystal field-cooled and zero-field-cooled magnetization data for the single-molecule magnet [Ni(hmp)(dmb)Cl](4) are presented that indicate the presence of ferromagnetic ordering at approximately 300 mK, which has little effect on the magnetization relaxation rates.

Superconductivity and the high-field ordered phase in the heavy-fermion compound PrOs4Sb12

Superconductivity is observed in the filled skutterudite compound PrOs4Sb12 below a critical temperature Tc = 1.85 K and appears to develop out of a nonmagnetic heavy Fermi liquid with an effective mass m ≈ 50 m e, where me is the free electron mass. Features associated with a cubic crystalline electric field are present in magnetic susceptibility, specific heat, electrical resistivity, and inelastic neutron scattering measurements, yielding a Pr3+ energy level scheme consisting of a Γ3 nonmagnetic doublet ground state, a low-lying Γ5 triplet excited state at ~10 K, and Γ4 triplet and Γ1 singlet excited states at much higher temperatures. Measurements also indicate that the superconducting state is unconventional and consists of two distinct superconducting phases. At high fields and low temperatures, an ordered phase of magnetic or quadrupolar origin is observed, suggesting that the superconductivity may occur in the vicinity of a magnetic or quadrupolar quantum critical point.

Magnetic-Field-Independent Ultrasonic Dispersions in the Magnetically Robust Heavy Fermion System SmOs4Sb12

Elastic properties of the filled skutterudite compound SmOs

f-Electron materials: a reservoir of novel electronic states and phenomena

_4

Crystalline Electric Field and Kondo Effect in SmOs4Sb12

Sb

Thermal and magnetic properties of the low-temperature antiferromagnetCe4Pt12Sn25

_{12}

Strongly correlated electron phenomena in Pr-based filled skutterudite compounds

have been investigated by ultrasonic measurements. The elastic constant

Quadrupolar susceptibility of NdOs4Sb12

C_{11}(\omega)

Investigation of magnetic order in Sm T r 2 Zn 20 ( T r = Fe , Co , Ru ) and Sm T r 2 Cd 20 ( T r = Ni , Pd )

shows two ultrasonic dispersions at

Novel strongly correlated electron states in filled skutterudite lanthanide osmium antimonides

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