Electrically pumped shot-noise limited class A VECSEL at telecom wavelength

Area of Science:

• Optics and Photonics
• Semiconductor Lasers

Background:

• Vertical External Cavity Surface Emitting Lasers (VECSELs) are attractive for their scalability and integration potential.
• Achieving low noise operation, particularly shot-noise limited performance, is crucial for sensitive applications.

Purpose of the Study:

• To demonstrate shot-noise limited, Class A operation in an electrically pumped VECSEL.
• To explore the integration of noiseless laser oscillation in compact, low-power devices.
• To analyze the design constraints of electrically pumped VECSELs compared to optically pumped ones.

Main Methods:

• Fabrication of a VECSEL with a quantum well active medium on an InP substrate for telecom wavelengths.
• Optimization of cavity dimensions to achieve single-frequency Class A operation with a long, high-finesse cavity.
• Characterization of the laser's intensity noise spectrum.

Main Results:

• Achieved shot-noise limited operation in an electrically pumped VECSEL.
• Demonstrated single-frequency Class A operation without intracavity filters.
• Measured a relative intensity noise of -160 dB/Hz at a detected photocurrent of 3.1 mA.

Conclusions:

• Electrically pumped VECSELs can achieve high-performance, low-noise operation.
• The demonstrated technology is suitable for applications requiring low power consumption and small footprint.
• This work paves the way for integrating advanced noiseless laser sources into practical devices.