  With the feature of low-power magnetization manipulation at an ultrashort
time scale, all optical switching (AOS) has been propelled to the forefront in
investigations. To further speed up the magnetization reversal by manipulating
ultrashort optical pulses, in this paper, one single square-wave laser pulse
(SWLP) vie the combination of heating and Inverse Faraday Effect (IFE) is
explored to excite the reversal of magnetization in a Co/Pt system. Simulation
results show that the switching time of magnetization is 3 times faster than
the using of a traditional Gaussian wave laser pulse (GWLP) under the same
laser energy and pulse duration, and the threshold of AOS for the ferromagnet
is 0.67 mJ/cm2. We furthermore demonstrate that the "heat accumulating effect"
of laser-pulse is an important factor that influences the switching time, and a
SWLP has a larger effect of heat accumulating than a GWLP.
