Two-dimensional photonic crystal Bragg lasers with triangular lattice for monolithic coherent beam combining

Area of Science:

• Optoelectronics
• Photonics
• Semiconductor Lasers

Background:

• Photonic crystal (PC) lasers offer unique light confinement properties.
• Achieving single-mode, large-area, and high-quality beam output remains a challenge.

Purpose of the Study:

• To demonstrate an electrically pumped, single-mode, large-area, edge-emitting InGaAsP/InP two-dimensional PC Bragg laser.
• To investigate the performance of triangular-lattice PC Bragg lasers and compare them with rectangular-lattice designs.
• To achieve coherent combination of PC Bragg lasers for enhanced beam quality.

Main Methods:

• Fabrication of InGaAsP/InP two-dimensional PC Bragg lasers with triangular lattice.
• Characterization of single-mode operation, far-field patterns, and performance metrics.
• Coherent combination of two single triangular-lattice PC Bragg lasers.

Main Results:

• The triangular-lattice PC Bragg laser operated in single transverse and longitudinal modes with a near-diffraction-limited, single-lobe far field.
• Performance was comparable to rectangular-lattice PC Bragg lasers.
• Coherent combination of two lasers yielded a near-diffraction-limited output beam while maintaining single-wavelength operation.

Conclusions:

• Electrically pumped, single-mode, large-area InGaAsP/InP PC Bragg lasers with triangular lattice are feasible.
• Triangular and rectangular lattice designs show comparable performance.
• Coherent combination of PC Bragg lasers is a viable strategy for achieving high-quality, broad-area laser output.