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Annealing temperature and O2 partial pressure dependence of T(sub c) in HgBa2CuO(4+delta)Samples of HgBa2CuO(4+delta) (Hg-1201) were annealed under various conditions. After carefully controlling annealing time, annealing temperature (T(sub a)) and O2 partial pressure (P(sub 0)), we were able to find the reversible annealing conditions for Hg-1201. Under 1 atm O2 at 260 C less than or equal to T(sub a) less than or equal to 400 C, the obtained T(sub c) is nearly the same (approximately 97 K). However, it decreases quickly with T(sub a) greater than 300 C in high vacuum (P(sub 0) approximately 10(exp -8) atm), and reaches zero at T(sub a) = 400 C. On the other hand, T(sub c) decreases with the decrease of T(sub a) in high-pressure O2 (approximately 500 atm) and reaches approximately 20 K at about 240 C. In the entire annealing region, the oxygen surplus varies significantly from 0.03 to 0.4, and a wide range of T(sub c) variation (0 goes to 97 K goes to 20 K) was obtained with anion doping alone.
Document ID
19950061654
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Xiong, Q. (University of Houston, Houston, TX US, United States)
Cao, Y. (University of Houston, Houston, TX US, United States)
Chen, F. (University of Houston, Houston, TX US, United States)
Xue, Y. Y. (University of Houston, Houston, TX US, United States)
Chu, C. W. (University of Houston, Houston, TX US, United States)
Date Acquired
August 16, 2013
Publication Date
November 15, 1994
Publication Information
Publication: Journal of Applied Physics
Volume: 76
Issue: 10:00 PM
ISSN: 0021-8979
Subject Category
SOLID-STATE PHYSICS
Funding Number(s)
CONTRACT_GRANT: NAGW-977
CONTRACT_GRANT: NSF DMR-91-22043
Distribution Limits
Public
Copyright
Other

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