Temperature dependence of the electron paramagnetic resonance linewidth inNaV2O5 - art. no. 172409

The qualitative explanation of the temperature dependence of the linewidth of electron-paramagnetic resonance (EPR) in alpha'-NaV2O5 is proposed. Our simple theory is based on the effectively one-dimensional quantum descripti on of effective spin-spin interactions. We explain the high-temperature inc rease of the EPR linewidth with increasing temperature by the influence of the effective magnetic anisotropy of spin-spin interactions. The low-temper ature upturn of the temperature dependence of the EPR linewidth is explaine d by the effect of period doubling of the exchange interaction of the effec tive quasi-one-dimensional spin subsystems. Our theory does not demand the controversial presence of the staggered Dzyaloshinskii-Moriya interactions at high temperatures.