Pressure dependence of the superconducting critical temperature of HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+{ital y}} and HgBa{sub 2}Ca{sub 3}Cu{sub 4}O{sub 10+{ital y}} up to 30 GPa

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.4265· OSTI ID:286697

Jover, D T; Wijngaarden, R J; Wilhelm, H; Griessen, R ^[1]; Loureiro, S M; Capponi, J ^[2]; Schilling, A; Ott, H R ^[3]

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1. Department of Physics and Astronomy, Free University, De Boelelaan 1081, 1081 HV Amsterdam (The Netherlands)
2. Laboratoire de Crystallographie, CNRS, Boite Postale 166, 38042 Grenoble (France)
3. Laboratorium fuer Festkoerperphysik, Eidgenoessische Technische Hochschule Hoenggerberg, 8093 Zuerich (Switzerland)

By performing experiments on samples as pure as presently available, the origin of the reported pressure-induced {ital T}{sub {ital c}} values well above 150 K in the mercury-based high-{ital T}{sub {ital c}} superconductors has been investigated. For HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+{ital y}} (Hg-1223) maximum {ital T}{sub {ital c}} values between 142 K and 146 K are obtained under pressure up to 30 GPa, while for HgBa{sub 2}Ca{sub 3}Cu{sub 4}O{sub 10+{ital y}} (Hg-1234) {ital T}{sub {ital c}} never exceeds 121 K. To verify the reproducibility between different laboratories the pressure dependence of a sample from the same batch as the sample on which Nu{tilde n}ez-Regueiro reported a {ital T}{sub {ital c}} value of 157 K at 23.5 GPa has also been measured. Below 10 GPa the agreement with his results is rather good and a possible explanation for the disagreement above 10 GPa is given. It appears that the reported high {ital T}{sub {ital c}} values in non-single-phase Hg-1223 samples are due to the presence of Hg-1234 phase impurities. Also some of the adopted definitions of {ital T}{sub {ital c}} have led to somewhat optimistic values of {ital T}{sub {ital c}}: The high-pressure results on Hg-1223 found in the literature are therefore reviewed and reanalyzed. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 286697
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 6 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
CALCIUM OXIDES
CHARGE DISTRIBUTION
COPPER OXIDES
ELECTRON TRANSFER
ELECTRONIC STRUCTURE
HIGH-TC SUPERCONDUCTORS
MERCURY OXIDES
PRESSURE DEPENDENCE
TRANSITION TEMPERATURE
VERY HIGH PRESSURE