Giga bit transmission in high-bandwidth low-loss perdeuterated polymer base graded-index polymer optical fiber link

This paper describes the high speed transmission characteristics of the perdeuterated poly methyl methacrylate (PMMA-d8) base graded-index (GI) polymer optical fiber (POF). The PMMA-d8 base GI POF was obtained by the interfacial-gel polymerization technique. We succeeded in 1 Gb/s 160 m transmission at 650-nm wavelength in the 160-m GI POF link. In general, the possible transmission distance of the PMMA POF link is limited to approximately 100 m because of high attenuation. However, substitution of hydrogen atoms in the polymer for deuterium atoms decreases the intrinsic absorption loss. The total attenuation of the PMMA-d8 base GI POF at 650-nm wavelength was about 60 dB/km which is approximately half of the attenuation of PMMA base GI POF. Therefore the low-loss PMMA-d8 base GI POF enables longer distance communication. We also analyzed the dispersion property of the PMMA-d8 base GI POF by utilizing WKB method in which both modal and material dispersion were taken into consideration. It was clarified that approximately 2 Gb/s transmission can be achieved by the PMMA-d8 base GI POF with 200-m length when 650-nm wavelength is adopted as the signal wavelength. The PMMA-d8 base fiber has two optical windows of light transmission which are located around 650-680-nm and 780-nm wavelengths. As the material dispersion decreases with increasing the signal wavelength, the use of the light source operating at 780 nm is effective for higher bit rate transmission. It was also confirmed that the PMMA-d8 base GI POF can transmit about 3 Gb/s for 200 m when the signal wavelength is 780 nm. These experimental and theoretical results indicate that the PMMA-d8 base GI POF could be one of the promising candidate of the physical layers in the high speed multimedia network.