High-power single-mode 1.3 µm semiconductor laser with a photonic crystal structure fabricated by standard lithography

A high-power single-mode semiconductor laser with a photonic crystal structure is demonstrated.The high-order surface gratings are designed as longitudinal photonic crystals to introduce distributed reflection defects.A broad ridge is employed to enhance output power, accompanied by two sets of transverse photonic crystals on either side to filter out high-order lateral modes.At an injection current of 700 mA, the output power of the laser reaches 120 mW, featuring a single-flap horizontal far-field (HFF) distribution with a full width at half-maximum (FWHM) of only 8.8°.The lasing wavelength is 1.3 μm with a side-mode suppression ratio (SMSR) of up to 41.74 dB.The fabrication process is based on standard lithography, and it avoids the need for high-precision lithography and regrowth techniques and provides a cost-effective and simple-process solution for single-mode lasers.