Phonon spectra and lattice specific heats of the thallium-based high-temperature superconductors

A. D. Kulkarni; F. W. de Wette; J. Prade; U. Schröder; W. Kress

doi:10.1103/PhysRevB.43.5451

← Back to search

Phonon spectra and lattice specific heats of the thallium-based high-temperature superconductors

A. D. Kulkarni, F. W. de Wette, J. Prade, U. Schröder, W. Kress

DOI 10.1103/PhysRevB.43.5451 · Physical Review B

T1

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 the phonon-dispersion curves, the one-phonon densities of state, the lattice specific heat cv(T), and the Debye temperatures FTHETA(T) of the thallium-based high-temperature superconductors, based on full lattice dynamical calculations. Repelling effects due to hybridization of the low-lying transverse acoustic and optical modes lead to small Debye regions of the specific heat (≤4 K), while the occurrence of low-lying dispersionless transverse modes in the outer parts of the Brillouin zone causes large drops in the Debye temperatures FTHETA(T) in the range 0 to 20 K. These effects are extremely pronounced in Tl2Ca2Ba2Cu3O10 because of the appearance of very-low-frequency modes.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Tl2Ba2CuO6 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Tl2CaBa2Cu2O8 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Tl2Ca2Ba2Cu3O10 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
TlCaBa2Cu2O7 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
TlCa2Ba2Cu3O9 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
TlCa3Ba2Cu4O11 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
La2-xSrxCuO4 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
YBa2Cu3O7 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2CaSr2Cu2O8 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown