The physical properties and structural evolution of the 122-type solid solution BaNi 2(Ge 1-xP x) 2 are reported. The in-plane X-X (X = Ge 1-xP x) dimer formation present in the end member BaNi 2Ge 2, which results in a structural transition to orthorhombic symmetry, is completely suppressed to zero temperature on P substitution near x=0.7, and a dome-shaped superconducting phase with a maximum T c=2.9 K emerges. Clear indications of phonon softening and enhanced electron-phonon coupling are observed at the composition of the structural instability. Our findings show that dimer breaking offers possibilities as a tuning parameter of superconductivity.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Sep 19 2012|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics