HIGH-PRESSURE NMR OF HEAVY-FERMION ANTIFERROMAGNETS CEAL2 AND CECUAL3

We have studied high pressure effects on heavy fermion antiferromagnet s CeAl2 and CeCuAl3 by NMR up to 15kbar. In CeAl2 the Al-27 Knight shi ft K(proportional to chi) decreased remarkably with increasing pressur e p, indicating marked increase of T-K with p. With decrease of T-N by p, a transition from modulated to type II ordering was obserbed for p greater than or equal to 12kbar by NMR below T-N. CeCuAl3 (T-N=2.5K) was affected much sensitively by p, as T-N disappeared for p greater t han or equal to 12kbar.