Observation of spin freezing and relaxation at microwave frequencies in the spin ladder compound $S{r}_{14-x}C{a}_{x}C{u}_{24}{O}_{41}$

Z. Zhai, P. V. Patanjali, N. Hakim +5

We report the observation of a frequency ($\omega$) and temperature (T) -dependent loss peak in ${\chi }^{\prime \prime }$ and accompanying dispersion in ${\chi }^{\prime }$ from microwave (2-18GHz) measurements of the co…