Magnetic relaxation phenomena in a CuMn spin glass

Experiments on the temperature and time dependence of the response function and the field cooled magnetisation of a Cu(Mn) spin glass at temperatures below the zero field spin glass temperature are used to explore the non-equ ilibrium nature of the underlying spin configuration. The results imply tha t a certain spin configuration is imprinted on the system as the temperatur e is decreased at a constant cooling rate. The cooling rate governs the mag nitude of the FC magnetisation (M-FC(H,T)). Any intermittent halt at a cons tant temperature, T-i, imprints an extended spin configuration, a process t hat is reflected e.g. in a downward relaxation of M-FC. On continued coolin g at the same rate, the magnitude of M-FC(T) remains at a lower level than that of a continuous cooling curve. These results are put into the context of the corresponding behaviour of the response function as observed in meas urements of the relaxation of the zero field cooled magnetisation.