OBSERVATION OF DIAMAGNETIC DOMAINS IN BERYLLIUM BY MOON SPIN ROTATIONSPECTROSCOPY

Spectroscopic evidence is given for the recurrent ''domain phase'' wit h oppositely magnetized regions in diamagnetic beryllium. A periodic s plitting of the precession frequency of implanted muons in a Be single crystal was observed as the strength of the applied field H parallel to {0001} varied near H-0 = 2.74 T. On sweeping H downwards, the doubl et emerges and persists within more than one third of each de Haas-van Alphen cycle, the positions of the lines fixed, with the lower freque ncy (diamagnetic) component gaining and the higher (paramagnetic) one losing intensity. The line splitting gives Delta B approximate to 29 G for the induction difference in domains at T = 0.8 K.