Phonon density of states, anharmonicity, electron-phonon coupling, and possible multigap superconductivity in the clathrate superconductors Ba8Si46 and Ba24Si100: Factors behind large difference in Tc
Rolf Lortz, Romain Viennois, Alexander Petrovic, Yuxing Wang, Pierre Toulemonde, Christoph Meingast, Michael Marek Koza, Hannu Mutka, Alexei Bossak, Alfonso San Miguel
DOI 10.1103/PhysRevB.77.224507 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
We report a detailed study of specific heat, electrical resistivity, and thermal expansion in combination with inelastic neutron and inelastic x-ray scattering to investigate the origin of superconductivity in the two silicon clathrate superconductors Ba8Si46 and Ba24Si100. Both compounds have a similar structure based on encaged barium atoms in oversized silicon cages. However, the transition temperatures are rather different: 8 and 1.5 K, respectively. By extracting the superconducting properties, phonon density of states, electron-phonon coupling function, and phonon anharmonicity from these measurements, we discuss the important factors governing Tc and explain the difference between the two compounds.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| Ba8Si46 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 8.1 | Pressure not reported | midpoint |
| Ba24Si100 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 1.55 | Pressure not reported | midpoint |
Similar papers
Phonon density of states, anharmonicity, electron-phonon coupling and possible multigap superconductivity in the clathrate superconductors Ba8Si46 and Ba24Si100: Why is Tc different in these two compounds?
similarity 0.99Rolf Lortz et al. · 2008 · arXiv:0804.0535
Source status unknown — claims are unverified
Superconductivity and physical properties of Ba24Si100 determined from electric transport, specific-heat capacity, and magnetic susceptibility measurements
similarity 0.96Takeshi Rachi et al.
Source status unknown — claims are unverified
Two energy gaps in the tunneling-conductance spectra of the superconducting clathrate Ba8Si46
similarity 0.94Yves Noat et al.
Source status unknown — claims are unverified
Superconductivity in Doped sp3 Semiconductors: The Case of the Clathrates
similarity 0.93D. Connétable et al.
Source status unknown — claims are unverified
Enhanced high-pressure superconductivity and local structure of the Ba8Si46 clathrate
similarity 0.93F. Morales et al.
Source status unknown — claims are unverified
Vibrational modes in silicon clathrate compounds: A key to understanding superconductivity
similarity 0.93E. Reny et al.
Source status unknown — claims are unverified