Anomalous Nuclear Relaxation and Knight Shift Behaviors of205Tl in High-TcTl2Ba2Ca1Cu2O8+δ
- 15 September 1988
- journal article
- letter
- Published by Physical Society of Japan in Journal of the Physics Society Japan
- Vol. 57 (9) , 2893-2896
- https://doi.org/10.1143/jpsj.57.2893
Abstract
The nuclear relaxation rate, 1/ T 1 , and Knight shift have been investigated between 4.2 K and 300 K by 205 Tl nuclear magnetic resonance (NMR) for Tl 2 Ba 2 Ca 1 Cu 2 O 8+δ with T c =100 K. It has been observed that there are two Tl sites possessing a different electronic state. The distinct decrease of 1/ T 1 and Knight shift for both Tl sites has been found just below an onset temperature of T 0 =115 K rather than a zero-resistance temperature of T c =100 K. Above T 0 , 1/ T 1 is not of the Korringa-type with T 1 T =const., but exhibits weak temperature dependence, resembling the behavior of the CuO 2 plane site of YBa 2 Cu 3 O 7 . The 1/ T 1 for Tl sites possessing no magnetic moments is demonstrated to reflect the strong spin correlation above T 0 through the hybridization with the Cu d-wave function.Keywords
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