50 K enhancement of Tc by pressure in the Hg-2212 superconductor

ACHA, C.; LOUREIRO, S.M.; CHAILLOUT, C.; THOLENCE, J.L.; CAPPONI, J.J.; MAREZIO, M.; NÚÑEZ-REGUEIRO, M.

SOLID STATE COMMUNICATIONS

PERGAMON-ELSEVIER SCIENCE LTD

Año: 1997 vol. 102 p. 1 - 5

0038-1098

The superconducting properties of mercury cuprates are extremely sensitive to compression. The highest transition temperatures obtained up to date have been measured on Hg-1223 at 25-30 Gpa (Tc ∼164 K at the onset) and imply an increase of about 20 K with respect to the ambient pressure Tc0. We report here the largest total pressure effect (> 50 K over a span of 20 GPa) ever observed for several samples of bi-mercury layer Hg2Ba2(Y1 - xCax)Cu2O8 - δ compositions. Different Ca doping levels give different initial Tcs but retain the same strong pressure dependence. The large Tc increase with pressure for all the Hg-based compounds, independently of their doping level, is revealing the existence of a common structural parameter, which identification will be a guide for future synthesis efforts of record-high Tc materials. © 1997 Elsevier Science Ltd. All rights reserved.