Abstract

We demonstrate that an optical wave propagating through a polarization and modal scrambling multimode fiber can regain its original polarization state by phase conjugation followed by reverse propagation through the medium.^1,2 Such a polarization recovery phenomenon is achieved even when magnetic field is applied along the fiber.³ The experimental arrangement is described as follows: the output light from the argon-ion laser was coupled Into a graded-index multimode fiber (100-μm core diam, 20-m length). A section with a length of ~3 m of the fiber was placed in a uniform magnetic field. The output of the fiber was focused onto a BaTiO₃ crystal which aligned to form a self-pumped phase conjugate mirror.⁴ The reflected phase conjugate light was linearly polarized along the x axis and coupled back into the fiber automatically. The polarization state of the phase conjugate light after passing through the fiber, was analyzed. The interesting and significantly new observations are that:

© 1986 Optical Society of America