Metallic-glass fiber-optic phase modulators.
Three different optical-fiber phase modulators utilizing the magnetostrictive properties of a metallic-glass alloy were constructed. By binding the optical fiber to the magnetostrictive metallic glass, the strain induced in the metallic glass that is due to the magnetic field is transferred to the optical fiber. Two ring and one flat linear modulator configurations were investigated. Each modulator's performance was evaluated by measuring the induced phase shift as a function of the excitation frequency of the magnetic field normalized by the fiber length. The highest sensitivity of 75 mrad/cm-Oe was attained for the linear modulator.
Trowbridge
F R
FR
Phillips
R L
RL