Polarization Effects in Optical Fiber Links

Abstract

Axis x and y are the initial, unrotated axes, ξ and η are a new set of axes along the rotated. 2. The area of polarization ellipse depends on the lengths of major and minor axes, amplitudes E 0x and E 0y and phase shift ϕ. 3. The angle β p =arctg(E 0y /E 0x) is called the auxiliary angle (0≤ψ≤π/2). 4. The rotation angle ψ (-β p ≤ψ≤β p) is the angle between axis x and major axis ξ. This angle is called the azimuth angle. 5. The ellipticity is the major axis to minor axis ratio (b/a).

Novel Polarization Control Approach to Long-Term Fiber-Optic Frequency Transfer

“…[9,10] However, due to the non-polarizationmaintaining characteristics of the conventional singlemode fiber, the state of polarization (SOP) of the transmitted laser may drift dramatically, and even degrade, [11,12] due to, e.g., environmental temperature fluctuations and stress along the fiber link. [13] In a typical optical frequency transfer system, two Faraday mirrors are respectively applied at a local site and a remote site to ensure that the reflected laser and the reference laser maintain a fixed polarization state. [14,15] Nonetheless, the transmitted laser at the remote site still experiences a deterioration in the SOP, which can interrupt the out-loop frequency measurement.…”