1-3hit |
Fumio KOYAMA Susumu KINOSHITA Kenichi IGA
This is the first report on room temperature CW operation of GaAlAs/GaAs vertical Fabry-Perot cavity surface emitting lasers. A vertical microcavity was formed with a diameter of 7 µm and cavity length of 5.5 µm by a two-step MOCVD growth and fully monolithic technology. The threshold current was 32 mA under CW condition at 22.5. Stable single transverse and longitudinal mode operation was obtained.
Masuo SUYAMA Takahumi TERAHARA Susumu KINOSHITA Terumi CHIKAMA Masaaki TAKAHASHI
We describe 2.5Gb/s 4 channel WDM transmission over 1060km using 18 EDFAs. Gain bandwidth narrowing in concatenated EDFAs has been successfully suppressed using unsaturated EDFAs and a 1.53µm ASE rejection filter.
Goji NAKAGAWA Yutaka KAI Kyosuke SONE Setsuo YOSHIDA Shinsuke TANAKA Ken MORITO Susumu KINOSHITA
We have designed and fabricated a compact 4-array integrated SOA module using a novel parallel optical coupling scheme and polarization-insensitive built-in array isolators. We achieved ultra-high On/Off extinction ratio of more than 60 dB and low cross talk of better than -60 dB as well as high-isolation of over 47 dB in wide wavelength ranges. We also developed a wavelength-insensitive parallel optical coupling scheme and an efficient thermal dissipating structure for a 4-array SOA module. We applied these technologies into 4-array SOA module fabrication and demonstrated a uniform optical coupling with the loss variance of 1 dB over the 140-nm wavelength ranges. We also demonstrated simultaneous operation of 300 mA 4 channels with low thermal degradation of the module gain less than 1 dB.