Switchable double wavelength generating vertical external cavity surface-emitting laser.

Area of Science:

• Optics and Photonics
• Semiconductor Lasers

Background:

• Vertical external cavity surface-emitting lasers (VECSELs) offer potential for tunable wavelength generation.
• Achieving multiple, switchable wavelengths from a single VECSEL chip remains a challenge.

Purpose of the Study:

• To demonstrate switchable dual-wavelength generation from a single VECSEL chip.
• To investigate the effect of pump power on wavelength switching in a two-mode resonant microcavity.

Main Methods:

• Fabrication of a VECSEL chip with a single set of quantum wells within a two-mode resonant microcavity.
• Utilizing pump power modulation to induce wavelength switching.
• Characterizing the output power and wavelengths of the generated laser emission.

Main Results:

• Demonstrated switchable generation of two distinct wavelengths (λ≈967 nm and 1,018 nm) from a single VECSEL chip.
• Achieved an output power of approximately 0.5 W for both wavelengths, with a spectral distance of 51 nm.
• Confirmed that pump power changes alter the active region temperature, spectrally tuning the gain spectrum to one of the two cavity modes.

Conclusions:

• Pump power modulation is an effective method for achieving switchable dual-wavelength operation in VECSELs.
• The demonstrated VECSEL design enables flexible wavelength selection within a single device.
• This technology holds promise for applications requiring tunable or multiple laser wavelengths.