Аннотации:
The spin relaxation of Yb3+-ions due to their coupling to antiferromagnetic spin waves existing in CuO2 planes in YBa2Cu3O6+y compound is reported. It is shown that it results in a strong temperature dependence of electron paramagnetic resonance (EPR) linewidth. The temperature dependence of EPR g-factor was also obtained and shows a good agreement with experimental data.