... Injection propertiesof n-AlxGa1ÀxAs-p-GaAs heterojunctions, Soviet Phy. Semicon., 2 (10) , 3733–3740, 1969.15. Neumann, E. G., Single-mode Fibers: Fundamentals, Springer-Verlag, Berlin, 1988.16. ... these grating structures, it isquite usual to have anti-reflective coatings on the laser facets of DFB and DBR lasers.The working principle of a uniform-grating DFB laser with perfectly anti-reflective ... Okamoto, K. and Sasaki, Y., Polarization-maintaining fibers and their applications,J. Lightwave Technol., LT-4 , 107 1 108 9, 1986.17. Bell, T. E., Single-frequency semicondcutor lasers, IEEE Spectrum,...