High-power and large-alignment-tolerance fiber coupling of honeycomb-lattice photonic crystal Γ-point band-edge laser

Butt-end fiber coupling is a compact and efficient scheme especially suitable for a surface-emitting photonic crystal (PC) band-edge laser. The honeycomb-lattice PC offers a relatively large intact area without air-holes, and therefore, a high optical gain. The use of a Γ-point band-edge mode allows vertical laser emission, yielding a fiber-coupled output power of more than 30 μW. The system is virtually alignment-free in the lateral directions; however, it exhibits oscillatory decay in the vertical direction, which can be significantly suppressed by using an angle-cleaved fiber tip.