Superconductivity under pressure of La2−xBaxCuO4 (0.05≤x≤0.25) and Nd1.85Ce0.15CuO4−δ

W. J. Liverman; J. G. Huber; A. R. Moodenbaugh; Youwen Xu

doi:10.1103/PhysRevB.45.4897

← Back to search

Superconductivity under pressure of La2−xBaxCuO4 (0.05≤x≤0.25) and Nd1.85Ce0.15CuO4−δ

W. J. Liverman, J. G. Huber, A. R. Moodenbaugh, Youwen Xu

DOI 10.1103/PhysRevB.45.4897 · 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

The superconducting transition temperature T versus pressure p (<18 kbar) was determined for La2−xBaxCuO4 (x=0.05, 0.08, 0.12, 0.125, 0.145, 0.175, and 0.25) and for Nd1.85Ce0.15CuO4−δ. The pressure was applied hydrostatically. Transition temperatures were determined using a mutual-inductance technique. For the Ba system, Tc’s rise under pressure. The highest dTc/dp (0.6 K/kbar) was observed for compositions x=0.12 and 0.125 at which the Tc at zero pressure is below 4 K. The results are compared with previous results for Ba and for Sr. Our results for x=0.12 and 0.125 (broad transitions, an apparently smooth increase in Tc with pressure, and Tc’s relatively low at all pressures) suggest that samples do not transform to a (higher-Tc) crystallographic phase under pressure. The Tc for Nd1.85Ce0.15CuO4 is found to be essentially pressure independent.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
La2-xBaxCuO4 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	4	Pressure unresolved	onset
Nd1.85Ce0.15CuO4-δ Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure unresolved	midpoint