A tunable pulsed laser includes a seed source and an optical circulator. The links can be used to construct an arm with multiples of three degrees of movement. The luminance signal Y2 and the luminance signal Y3 are mixed by a mixer, and a luminance signal having a frequency characteristic located between a frequency characteristic of the luminance signal Y2 and a frequency characteristic of the luminance signal Y3 is output. The alloy is further annealed with or without magnetic field at temperatures below said alloy’s first crystallization temperature, having rounded or rectangular or sheared or linear B-H hysteresis loops. A blowing fan mounted to a front end of the rotating shaft cools electrical devices and ventilates a cooking cavity of the microwave oven.