Birefringence Analysis of Photonic-Bandgap Fibers Using the Hexagonal Yee's Cell Aghaie, K. Z. ; Fan, Shanhui ; Digonnet, M. J. F. Abstract Publication: IEEE Journal of Quantum Electronics Pub Date: June 2010 DOI: 10.1109/JQE.2010.2040369 Bibcode: 2010IJQE...46..920A