Photonic crystal light-emitting sources.

Area of Science:

• Photonics
• Materials Science
• Optoelectronics

Background:

• Photonic crystals (PhC) enable control over spontaneous emission (SpE) in terms of direction and rate.
• Real-world light-emitting structures face numerous material and design constraints.

Purpose of the Study:

• To review and discuss the application of photonic crystals for practical light-emitting sources.
• To analyze various PhC-based approaches, considering real-world constraints and material limitations.

Main Methods:

• Discussion of mechanisms involving modified photonic bands and band gaps for light sources.
• In-depth analysis of planar emitters, grating diffraction for enhanced light extraction, and III-V/III-nitride semiconductor applications.
• Review of advanced structures, etched active structures, and the Purcell effect, including plasmonic implementations.

Main Results:

• Various PhC approaches demonstrate potential for controlling SpE in light sources.
• Grating diffraction enhances light extraction, with applications in III-V and III-nitride semiconductors.
• The Purcell effect shows promise for enhancing SpE rates, but is effective only for specific sources.

Conclusions:

• Successful implementation of PhCs for light sources requires a careful balance of physics and material parameters.
• Understanding physical limitations, including comparison with random surface roughening, is crucial.
• Advanced designs and consideration of plasmonic effects offer further avenues for SpE enhancement.