Kazutaka Takeda

1.2 µm Band GaInAs/GaAs High-Density Multiple-Wavelength Vertical Cavity Surface Emitting Laser Array

We demonstrate a densely packed multi-wavelength GaInAs/GaAs vertical cavity surface emitting laser array emitting in 1200 nm wavelength band. 110-channel emitters could be integrated in a 2.2 mm long bar with spatial spacing of 20 µm and wavelength spacing of 0.1 nm. All the emitters exhibit single mode operation with output power of over 1 mW. The wavelength separation is precisely controlled by adjusting the bias current of each element.

Wavelength Extension Effect on Lasing Characteristics of Highly-Strained GaInAs/GaAs Vertical-Cavity Surface-Emitting Lasers with Cavity Detuning

Cavity detuned highly-strained GaInAs/GaAs vertical cavity surface emitting lasers (VCSELs) were investigated. Devices emitting beyond 1.2 µm of the wavelength were realized by combining conventional quantum wells emitting at 1.18 µm and large wavelength detuned cavities. Various detuning conditions from -35 to 80 nm were compared for clarifying the detuning effect. The longest wavelength was 1.27 µm for an 80 nm detuned device. The highest operating temperature of a 55 nm detuned device was 140 °C under cw operation. It was found that approximately 50 nm detuning was necessary to reach the threshold gain level for a large detuned device and the condition was produced by self-heating. Relaxation resonance frequencies were characterized and over 2 GHz was observed even for a 1.27 µm VCSEL.

Electro-thermal wavelength tuning of 1.2 /spl mu/m GaInAs/GaAs vertical cavity surface emitting laser array

This paper demonstrates an electro-thermally tunable VCSEL array with an additional tuning electrode. The VCSEL array achieves continuous wavelength tuning of approximately 3 nm with a single-tuning-contact. The deviation in output power is within 1 dB. The power consumption for wavelength tuning is as low as 46 mW. Fast tuning response is expected in the proposed tunable VCSEL because of the small thermal capacity.

Characteristics and Reliability of 10 Gbps/Channel 1 ×10 Vertical-Cavity Surface-Emitting Laser Array of 850 nm Wavelength

A 10 Gbps/channel 1 ×10 vertical-cavity surface-emitting laser (VCSEL) array of 850 nm wavelength was demonstrated for a 100 Gbps (10 Gbps × 10) local area network. The VCSEL array was oxidized using an in situ probing technique. The threshold current of each VCSEL on the array is approximately 0.5 mA with the oxide and metal apertures of 8 and 6 µm, respectively. The temperature characteristic of lasing from -40 to 120 °C was stable and the f-3 dB cutoff frequency exceeded 10 GHz at 6 mA. The data transmission test through the conventional multimode fiber of 300 m length was carried out. We also investigated the reliability of the VCSEL array at an ambient temperature of 120 °C and a dc current of 15 mA. We could achieve a failure rate over a decade below 1% at a temperature and current of 60 °C and 7 mA, respectively.

High-temperature operation of a 1.2-μm single-transverse-mode highly strained GaInAs/GaAs QW laser

We presented the high temperature operation of 1200-nm band highly strained GaInAs/GaAs ridge-waveguide lasers. Active layer consists in three quantum wells with highly strained GaInAs. The In composition is 32%. The maximum operating temperature reaches at over 200°C and temperature characteristic T0 is 222K at 30-80°C with continuous wave operations, showing excellent temperature characteristics of highly strained QWs. We obtained a relaxation oscillation frequency of 2 GHz at 170°C.

Highly strained GaInAs/GaAs 1.21 /spl mu/m vertical cavity surface emitting laser with single-mode output power of 3 mW

A highly strained GaInAs/GaAs VCSEL emitting at 1.21 /spl mu/m is demonstrated. The threshold current is 1.3 mA. The maximum single mode output power of 3 mW is achieved. These results indicate that a highly strained 1.2 /spl mu/m range GaInAs VCSEL can be useful for high capacity metro-area networks.

1.2 /spl mu/m band high-density multiple-wavelength vertical cavity surface emitting laser array

A 1.2 /spl mu/m band densely packed VCSEL array with highly strained GaInAs/GaAs QWs with spatial spacing of 20 /spl mu/m and wavelength spacing of 0.1 nm is demonstrated for the first time. A large number of VCSELs of over 100 elements could be integrated in a 2 mm long bar.