Absence of gross static inhomogeneity in cuprate superconductors

J. W. Loram; J. L. Tallon; W. Y. Liang

doi:10.1103/PhysRevB.69.060502

← Back to search

Absence of gross static inhomogeneity in cuprate superconductors

J. W. Loram, J. L. Tallon, W. Y. Liang

DOI 10.1103/PhysRevB.69.060502 · 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

Recent scanning tunnelling microscopy (STM) studies on Bi2Sr2CaCu2O8+δ (Bi-2212) revealed the presence of severe inhomogeneity with a length scale L0≈ξ0, the coherence length. Other studies have been interpreted in terms of mesoscale or nanoscale phase segregation. Here we analyze heat capacity and NMR data on Bi-2212 and (Y,Ca)Ba2Cu3O7−δ and find no evidence of phase segregation or gross inhomogeneity. For Bi-2212 the coherence scale L0 increases with doping from 5ξ0 to 17ξ0 and the hole density inhomogeneity decreases from 0.028 to 0.005 holes/Cu. We conclude that STM measurements considerably overstate the inhomogeneity in bulk Bi-2212.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Bi2Sr2CaCu2O8+δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Y0.8Ca0.2Ba2Cu3O7 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
YBa2Cu3O6.92 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Bi2.1Sr1.9CaCu2O8 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown