Abstract
We have studied the effect of Ge substitution and pressure on the heavy-fermion superconductor . Ge substitution on the Si site acts as negative chemical pressure leading to an increase in the unit-cell volume but also introduces chemical disorder. We carried out electrical resistivity and ac heat-capacity experiments under hydrostatic pressure on . Our experiments show that the suppression of superconductivity in is mainly caused by the scattering potential, rather than volume expansion, introduced by the Ge dopants. The antiferromagnetic order is essentially not affected by the chemical disorder.
- Received 8 March 2010
DOI:https://doi.org/10.1103/PhysRevB.81.180511
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