TY  - JOUR
AU  - Jánossy, András
AU  - Brunel, LC
AU  - Cooper, Jr
TI  - Gd3+ ESR determination of the local spin susceptibility in Gd:YBa2Cu3Oy high-temperature superconductors
JF  - PHYSICAL REVIEW B
J2  - PHYS REV B
VL  - 54
PY  - 1996
IS  - 14
SP  - 10186
EP  - 10191
PG  - 6
SN  - 2469-9950
DO  - 10.1103/PhysRevB.54.10186
UR  - https://m2.mtmt.hu/api/publication/2609332
ID  - 2609332
AB  - Gd3+ ESR at high fields in Gd-doped high-T-c superconductors is shown to be a precise probe of the conduction electron static spin susceptibility, chi. The Gd3+ ESR Knight shift at 245 GHz and the spin relaxation broadening at 245 and 9.2 GHz in Gd0.01Y0.99Ba2Cu3Oy (with various values of between 6.05 and 7.0) are in agreement with published Y-89 NMR data above 70 K and provide additional measurements at the rare earth site at much lower temperatures. In the superconducting compounds chi(T) differs strongly from the Yoshida function and at low T it follows a T or T-2 dependence. An anomalous ESR line shape is found at low T in the superconducting state; we provisionally attribute this to a small (10(-2)-10(-3) mu(B)) static magnetic moment on planar Cu sites.
LA  - English
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Williams, GVM
AU  - Tallon, JL
AU  - Meinhold, R
AU  - Jánossy, András
TI  - 89Y NMR study of the effect of Zn substitution on the spin dynamics of YBa2Cu4O8
JF  - PHYSICAL REVIEW B
J2  - PHYS REV B
VL  - 51
PY  - 1995
IS  - 22
SP  - 16503
EP  - 16506
PG  - 4
SN  - 2469-9950
DO  - 10.1103/PhysRevB.51.16503
UR  - https://m2.mtmt.hu/api/publication/2609330
ID  - 2609330
AB  - Zn-substituted YBa2Cu4O8 high-temperature superconductors have been probed by 89Y nuclear magnetic resonance (NMR), susceptibility, and thermopower measurements. With 89Y NMR we have been able to study the gap in the spin density of states using the real part of the spin susceptibility determined from the Knight shift as Zn is progressively substituted onto the plane copper site. Zn substitution results in a rapid decrease in Tc with a negligible decrease in the spin-gap energy and an inhomogeneous filling in of the gap in spin density of states.
LA  - English
DB  - MTMT
ER  -