Electronic properties and superconductivity of rapidly quenched Al-Si alloys
J. Chevrier, D. Pavuna, F. Cyrot-Lackmann
DOI 10.1103/PhysRevB.36.9115 · 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 present detailed studies of electronic properties of Al-Si alloys prepared in a nonequilibrium state by means of rapid solidification. The quenched alloys exhibit an enhanced superconducting transition temperature up to 6.2 K in an Al–Si 30 at. % alloy as well as an increased thermal slope of resistivity. Using differential scanning calorimetry, a large enthalpy variation (ΔH=4.1 kJ/mole for Al–Si 30 at. %) has been measured during the irreversible transition from the non- equilibrium state to the equilibrium one. This is mainly attributed to the energy difference between the metallic state of silicon atoms trapped in fcc aluminum matrix during quenching and the usual covalent state of silicon precipitates in an equilibrium state. This large energy difference is presented as the origin of a lattice instability which softens the phonon spectrum and gives rise to a stronger electron-phonon coupling. This appears to be a characteristic property of nonequilibrium Al-Si solid solutions, which is associated with the metallic state of silicon atoms. An interpretation of the Tc enhancement is proposed for both Al-Si and Al-Ge alloys based on the phonon softening in these nonequilibrium crystalline alloys.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| Al-Si Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 6.2 | Pressure not reported | onset |
Similar papers
Superconducting energy gap from break-junction tunneling spectroscopy in the ternary silicide CaAlSi
similarity 0.91S. Kuroiwa et al.
Source status unknown — claims are unverified
Electronic structure and superconductivity of CaAlSi and SrAlSi
similarity 0.91I. I. Mazin & D. A. Papaconstantopoulos
Source status unknown — claims are unverified
Unveiling mechanisms of electric field effects on superconductors by a magnetic field response
similarity 0.91Lennart Bours et al.
Source status unknown — claims are unverified
Correlation between crystal structures of CaAlSi with and without superlattice and superconducting properties
similarity 0.91S. Kuroiwa et al.
Source status unknown — claims are unverified
Superconductivity induced by doping holes in the nodal-line semimetal NaAlGe
similarity 0.90Toshiya Ikenobe et al.
Source status unknown — claims are unverified
Superconductivity in Lithium, Potassium, and Aluminum under Extreme Pressure: A First-Principles Study
similarity 0.90G. Profeta et al.
Source status unknown — claims are unverified