Active Beam Steering Enabled by Photonic-Crystal Surface-Emitting Laser.

Area of Science:

• Optoelectronics
• Photonics
• Laser Physics

Background:

• Directional light emission is vital for applications like optical communication and displays.
• Existing directional emitters often use bulky, fragile components leading to power loss.
• A compact, integrated solution for controlled beam steering is needed.

Purpose of the Study:

• To theoretically propose and experimentally demonstrate a novel directional emitter using a single surface-emitting laser.
• To achieve dynamically controlled beam steering with a compact photonic crystal laser.
• To enable on-chip active beam steering for various applications.

Main Methods:

• Designed a surface-emitting laser based on photonic crystals operating near band edges.
• Quantized optical modes in three-dimensional momentum space by reducing laser size.
• Utilized luminescence spectrum shifting under current injection to select lasing modes.

Main Results:

• Demonstrated a single-mode operation with narrow line widths (minimum 1.8 MHz) and ~10 milliwatts output power.
• Achieved fast beam steering over a 3.2° × 4° range within 500 ns.
• Validated the directional radiation of quantized optical modes toward the far-field.

Conclusions:

• The proposed photonic crystal laser enables on-demand directional light emission and fast beam steering.
• This integrated approach overcomes limitations of traditional bulky directional emitters.
• The technology holds promise for automotive, industrial, and robotic applications requiring precise light control.