Research on the phase properties of 2×2 single-mode fiber coupler

• Published in: Optik (Stuttgart) Vol. 126; no. 2; pp. 289 - 291
• Main Authors: Hao, Yun-qi, Zhai, Feng-xiao, Yang, Kun
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 01.01.2015
• Subjects: 2 × 2 single-mode fiber coupler; Birefringence; Computer simulation; Fibers; Joining; Loss; Phase difference; Phase shift; Refractive index; Refractivity; Wavelengths; Birefringence; 2×2 single-mode fiber coupler; Phase difference; Loss
• ISSN: 0030-4026; 1618-1336
• DOI: 10.1016/j.ijleo.2014.08.163

The phase properties at the output ends of 2×2 single-mode fiber couplers are investigated in detail. Considering the coupler's loss but not the birefringence, the phase difference between the two output ends is studied. It shifts less than 3° from the phase difference without considering the loss. Taking account of the fiber's birefringence, the phase retardance between the two orthogonal components at the end of the throughout/coupled arms, the mathematical expression is given and influences of the working wavelength, the environment refractive index and the effective coupled length on the retardance are simulated. Error between theoretical results and experimental results is 7.374%. With a linear polarized light input, the output light develops into an elliptical polarization.