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A passively aligned VCSEL transmitter operating at fixed current over a wide temperature range
Jonghyun Park1, Taeyong Kim, Sung-Han Kim
1Department of Electrical and Computer Engineering, Ajou University, Suwon, Gyeonggi, South Korea. whitebear80@gmail.com
Optics Express
|April 1, 2009
Summary
This study demonstrates a low-current Vertical-Cavity Surface-Emitting Laser (VCSEL) transmitter that operates reliably across a wide temperature range. Its stable performance enables low-power, cost-effective Gigabit Ethernet applications.
Area of Science:
- Optoelectronics
- Semiconductor Devices
Background:
- Vertical-Cavity Surface-Emitting Lasers (VCSELs) are crucial for optical communication.
- Optimizing VCSEL performance under varying temperatures is essential for reliable data transmission.
Purpose of the Study:
- To investigate the low-current operation of a passively aligned VCSEL transmitter.
- To evaluate its performance across a wide temperature range for potential applications.
Main Methods:
- Fabrication of GaAs/AlGaAs-based 850-nm oxide VCSELs.
- Testing the VCSEL transmitter's characteristics at fixed 'on' and 'off' currents.
- Characterizing threshold current and its temperature dependence (d(2)I(th)/dT(2)).
Main Results:
- Achieved a minimum threshold current of 0.79 mA at 50°C.
- Demonstrated a low temperature dependence of threshold current (d(2)I(th)/dT(2) as low as 0.114 μA/°C²).
- Verified compliance with Gigabit Ethernet standards from -20°C to 120°C.
Conclusions:
- The fabricated VCSEL transmitter exhibits superior temperature stability for fixed-current operation.
- This enables low-power consumption, low-cost, and passively aligned VCSEL transmitters.
- The findings support the development of robust optical communication modules for diverse environments.
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