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IJPAP Vol.45(01) [January 2007] >
| Title: | Phonons in non-oxide perovskite superconductor MgCNi₃ |
| Authors: | Sinha, M M |
| Keywords: | Lattice dynamics
Phonon spectra
Zone center phonons
Intermetalic compound |
| Issue Date: | Jan-2007 |
| Publisher: | CSIR |
| IPC Code: | H01L 39/00 |
| Abstract: | The new intermetallic non-oxide perovskite superconductor MgCNi₃ was discovered by He et al, Nature, 411(2001) 54, following on from the breakthrough of the finding of the MgB₂ superconductor at the beginning of 2001. MgB₂ has subsequently been intensively studied; however, less attention has been paid to MgCNi₃ due to its much lower superconducting transition temperature (Tc ~8 K), as compared to that of MgB₂ (Tc ~39 K). But it has many interesting properties, which need to be focused on to obtain an understanding of its complicated physics. Being a perovskite superconductor like Ba₁₋xKxBiO₃ and cuprate superconductors, MgCNi₃ is special it is neither an oxide nor does it contains any copper. Meanwhile, MgCNi₃ can be regarded as fcc Ni with only one quarter of Ni replaced by Mg and with C sitting on the octahedral sites. The fact that superconductivity rather than ferromagnetism occurs in a compound where so much nickel is present is surprising and suggest that MgCNi₃ is a candidate for exhibiting unconventional superconductivity. In this work, a de Launey angular force constant model has been used to study the phonons in MgCNi₃. The phonon dispersion curves in the symmetric directions are plotted and compared with available results. |
| Page(s): | 72-74 |
| ISSN: | 0019-5596 |
| Source: | IJPAP Vol.45(01) [January 2007]
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