Magnetic susceptibility of normal state and superconductivity of La2−xSrxCuO4

✍ Scribed by R. Yoshizaki; N. Ishikawa; H. Sawada; E. Kita; A. Tasaki

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 593 KB
• Volume: 166
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(90)90038-g

✦ Synopsis

The two-dimensional spin-correlation energy, J, was studied in La2_~rxCu04 by means of magnetic susceptibility measurements. We found that J, deduced from the susceptibility peak temperature, T_, changed drastically with the character of the doped holes, localized or itinerant. In the low carrier density region (O~x~O.O8), J was higher than 1000 K, representing the nearest neighbor interaction due to the localization of holes. A sudden drop of J and the appearance of bulk superconductivity were observed at x=0.09, which was ascribed to the itinerant holes. The Zn substitution effect for Cu was investigated near the superconductor-to-normal-metal transition. We found that only 1% Zn substitution resulted in 30% decrease of both T, and T_, and T,,,, disappeared as T, became zero. Those results give us direct evidence that the spin correlation relates to the appearance of the superconductivity.