25.8Gbps Direct Modulation AlGaInAs DFB lasers with Ru-doped InP Buried Heterostructure for 70°C operation
25.8Gbps Direct Modulation AlGaInAs DFB lasers with Ru-doped InP Buried Heterostructure were fabricated for the first time. The lasers achieved high output power and clear eye opening at 70°C and are promising for uncooled operation.
1.3-μm-Wavelength AlGaInAs Multiple-Quantum-Well Semi-Insulating Buried-Heterostructure Distributed-Reflector Laser Arrays on Semi-Insulating InP Substrate
1.3-μm-wavelength AlGaInAs distributed-reflector laser arrays on semi-insulating InP substrate for high-speed direct modulation are investigated to realize compact and low-power-consumptive optical modules. Combination of AlGaInAs quantum wells with large differential gain and semi-insulating buried-heterostructure for reduction of the volume in active region achieved high-speed direct modulation. The fabricated lasers in the array lase with different wavelengths with stable single-longitudinal mode. Clear eye-opening and large mask margin were obtained in push-pull driving at 25.8 Gb/s direct modulation with coplanar electrode and semi-insulating InP substrate. Comparison of modulation waveform under simultaneous operation of neighbor lasers shows that crosstalk between lasers in the array is small. Clear eye-openings, large mask margins, and 10-km fiber transmission of four different wavelength lasers on LAN-WDM grid are demonstrated under 28-Gb/s operation at 50 °C. For further high-speed operation, 43-Gb/s direct modulation were performed. These results indicate that the 1.3-μm AlGaInAs DR laser arrays are promising as light sources for 100-Gb/s Ethernet and higher speed transmission.
The Internet and the Changing Beijing-Taipei Relations: Toward Unification or Fragmentation?
Information and its technologies facilitate the exercise of what has been called “soft power,” a concept that differentiates information from the conventional dimensions of “hard power,” which is mainly associated with military force and economic influence. Soft power, according to Nye, a former Assistant Secretary of Defense of the United States, means that “A country may obtain the outcomes it wants in world politics because other countries want to follow it, admiring its values, emulating its example, aspiring to its level of prosperity and openness. In this sense it is just as important to set the agenda in world politics and attract others as it is to force them to change through the threat or use of military or economic weapons.”1