TY - JOUR
T1 - Annealing condition, Tc, and oxidation enthalpy in HgBa2CuO4+δ
AU - Xue, Y. Y.
AU - Xiong, Q.
AU - Chen, F.
AU - Cao, Y.
AU - Liu, L. M.
AU - Jacobson, A. J.
AU - Chu, C. W.
N1 - Funding Information:
This work is supported in part by NSF Grant No DMaR 91-22043, USAFOSR Grant No F49620-93-|-0310 by BMDO, the state of Texas through the Texas Center for Superconductivity at the University of Houston, and the T. L. L. Temple Foundation.
PY - 1994/12
Y1 - 1994/12
N2 - To obtain a broad range of Tc for HgBa2CuO4+δ (Hg1201) by annealing, the oxidation thermodynamics and oxygen diffusion have been studied. During annealing, δ is controlled by the oxygen partial pressure P(O2) as well as the annealing temperature Ta with the oxidation enthalpy ΔH and the oxidation entropy ΔS as key parameters. Our data suggest that the ΔH of Hg1201 significantly depends on δ, which makes the ∂δ/ ∂P(O2) of Hg1201 smaller than that of YBa2Cu3O7-δ in a practical Ta range. Therefore, a wider P(O2) range are necessary. By choosing proper annealing parameters, Hg1201 samples with 0 K ≤ Tc ≤ 97 K on the underdoped side and 97 K ≥ Tc ≥ 20 K on the overdoped side were obtained.
AB - To obtain a broad range of Tc for HgBa2CuO4+δ (Hg1201) by annealing, the oxidation thermodynamics and oxygen diffusion have been studied. During annealing, δ is controlled by the oxygen partial pressure P(O2) as well as the annealing temperature Ta with the oxidation enthalpy ΔH and the oxidation entropy ΔS as key parameters. Our data suggest that the ΔH of Hg1201 significantly depends on δ, which makes the ∂δ/ ∂P(O2) of Hg1201 smaller than that of YBa2Cu3O7-δ in a practical Ta range. Therefore, a wider P(O2) range are necessary. By choosing proper annealing parameters, Hg1201 samples with 0 K ≤ Tc ≤ 97 K on the underdoped side and 97 K ≥ Tc ≥ 20 K on the overdoped side were obtained.
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U2 - 10.1016/0921-4534(94)91675-6
DO - 10.1016/0921-4534(94)91675-6
M3 - Article
AN - SCOPUS:0039171665
VL - 235-240
SP - 901
EP - 902
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - PART 2
ER -