세라믹 초전도체 YBa_(2-X)Ca_(X)Cu_(3)O_(7-Y)의 특성 비교 = Comparative Analysis between the Characteristics of Ceramic Superconductor YBa_(2-X)Sr_(X)Cu_(3)O_(7-Y) and YBa_(2-X)Ca_(X)Cu_(3)O_(7-Y)

다국어 초록 (Multilingual Abstract)

Ceramic superconductors YBa_(2-X)(A)_(S)Cu_(3)O_(7-Y), where A=Ca or Sr, were made for several different values of X
X-ray powder diffraction, SEM, magnetigation, and resistivity versus temperature measurements were carried out to study the effects of Ca and Sr substitutions into 1:2:3 type superconductors on the superconducting characteristics.
Both ca and Sr substitutions were observed to observed to suppress the critcal temperatuse strongly, but Sr substitution seems to the more effective in the suppression mechanism.
The decrease of Tc seems to be due to the change in oxygen concentration induced by the Ca and/or Sr substitution.
This implies that the variation of critical temperature has close relation with that of mobile hole concentration in the Cu-O planes.

목차 (Table of Contents)

• I. 서론
• II. 시료제작 및 측정방법
• 1. 시료제작
• 2. 측정방법
• III. 결과 및 분석
• 1. X-선 회질
• 2. SEM
• 3. 자화곡선 및 초전도 전이온도
• 4. 전기저항 특성 및 임계온도 Tc
• IV. 결론
• 참고문헌