We demonstrate a high linear polarization, narrow linewidth hybrid laser composed of a semiconductor gain chip and a high birefringence waveguide Bragg grating (WBG). The laser operates in the C-band, and a maximum output power of 8.07 mW is obtained in the fiber waveguide. With careful temperature tuning, the hybrid laser can operate in a single longitudinal mode state from above the threshold current to 410 mA. The side mode suppression ratio (SMSR) reaches a value of 50.2 dB, and the polarization extinction ratio exceeds 39.6 dB. We numerically analyze the linewidth suppression for the Bragg grating based on adiabatic chirp theory. The hybrid laser shows a narrow linewidth of 4.15 kHz and a low relative intensity noise (RIN) of <-155 dBc/Hz, providing a high-performance light source for coherent light communication.

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High-birefringence waveguide Bragg gratings for the C-band are fabricated in the Silica-on-Silicon platform with Displacement Talbot Lithography (DTL). Transmission and reflection spectrums of the Bragg wavelength splitting were measured and calculated. The birefringence here is up to 7.919×10−4 to 1.670×10−3, much higher than existing devices via other platforms. We illustrate the principle and advantage of DTL though theoretical analysis and numerical simulation. The birefringence of waveguide Bragg gratings here are customized with their device configuration (i.e., waveguide width and grating etched depth), enabling an effective method to construct scalable Silica-on-Silicon devices for highly linear-polarized external-cavity semiconductor lasers.