Wavelength tuning robustness optimization for a high-temperature single-mode VCSEL used in chip-scale atomic sensing...

Area of Science:

• Optics and Photonics
• Semiconductor Devices
• Atomic Physics

Background:

• Atomic sensing systems require highly stable and precise laser sources.
• Vertical-cavity surface-emitting lasers (VCSELs) are promising for chip-scale integration due to their compact size and low cost.
• Maintaining laser stability, particularly wavelength precision, under varying operational temperatures is crucial for reliable sensing.

Purpose of the Study:

• To investigate the wavelength current tuning characteristics of high-temperature-operation single-mode VCSELs.
• To assess the impact of optimized oxide aperture size on laser performance and stability.
• To determine the suitability of these VCSELs for chip-scale atomic sensing applications.

Main Methods:

• Fabrication of single-mode VCSELs with an 8 µm oxide aperture.
• Optimization of oxide aperture size and implementation of surface relief mode control.
• Characterization of wavelength-current tuning behavior at elevated temperatures (up to 355 K).
• Measurement of output power and wavelength tuning coefficient.

Main Results:

• Achieved output power of 2.02 mW at 355 K for the optimized single-mode VCSEL.
• Demonstrated a robust wavelength current tuning coefficient of approximately 0.25 nm/mA.
• Observed low active current density and reduced device heat generation due to the optimized aperture size.

Conclusions:

• Optimized oxide aperture size in VCSELs significantly enhances wavelength current tuning robustness.
• These high-temperature-operation VCSELs exhibit excellent stability, making them suitable for chip-scale atomic sensing.
• The findings contribute to the development of more stable and reliable atomic sensing technologies.