The Competition between Staggered Field and Antiferromagnetic Interactions in CuGeO3:Fe

The EPR spectra along different crystallographic axes for single crystals of CuGeO 3 containing 1% of Fe impurity have been studied in the frequency range 60-360 GHz at temperatures 0.5-30 K. The analysis based on the Oshikawa-Affleck theory suggests that. the temperature dependences of the line width and g-factor are formed as a result of the competition between interchain antiferromagnetic interactions and staggered Zeeman energy. It is found that staggered magnetic moments in CuGeO 3 :Fe are located predominantly along b axis.