This paper reports the fabrication and characterization of a new type latching magnetic optical switch. The basic optical switch has two stable states wherein an optical signal from the input port can be routed to either one of the two output ports. The key component of the optical switch is a cantilever made of soft magnetic material with a reflective surface. The optical switch is bi-stable because the cantilever has a tendency to align with the external magnetic field, and the torque to align the cantilever can be di-directional depending on the angle between the cantilever and the magnetic field. Switching between the two stable states is accomplished by momentarily changing the direction and/or the magnitude of the cantilever's magnetization by passing a short current pulse through a planar coil underneath the cantilever. In either of its stable states, the cantilever is held in its position by the combined influence of permanent external magnetic field and other mechanical forces, such as a physical stop or a mechanical torques produced by torsion flexures supporting the cantilever. Large angle deflection and bi-stable latching operations have been demonstrated. Characterization has been performed for optical switching performances. Computer simulation results were compared to the experimental results. The switching speed is 3.2 ms, optical insertion loss is -4 dB, and the energy consumption is 44 mJ for each switching event.
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