We have found a staircase-like hysteresis loop in III-V compound diluted ma
gnetic semiconductor (In,Mn)As in magneto-transport behavior below 1 K. The
observed stepwise changes are attributed to the corresponding jumps in mag
netization and are associated with the depinning process of domain walls. W
e discuss thermal avalanche effect and quantum tunneling, (C) 2000 Elsevier
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