Reorientation of the B-H complex in silicon by anelastic relaxation experiments

An increase of the acoustic absorption is found in La2-xSrxCuO4 (x=0.019, 0.03, and 0.06) close to the temperatures at which freezing of the spin fluctuations in antiferromagnetic-correlated clusters is expected to occur. The acoustic absorption is attributed to changes of the sizes of the quasifrozen clusters induced by the vibration stress through magnetoelastic coupling.