  We study thermally assisted domain wall generation in perpendicular magnetic
anisotropy CoFeB trilayer nanowires by the effect of Joule heating. The
anomalous Hall effect is utilized to detect magnetization reversal in order to
study the domain wall generation. We observe a statistical distribution in the
switching process which is consistent with the thermal activation process. Our
results show that the proposed method provides an efficient way for generating
domain walls in perpendicular magnetic nanowires at predefined locations.
