Embodiments are provided for an optical coupler created by bonded photonic chip coupler for Silicon-on-Insulator (SOI) chip-fiber coupling. System and apparatus embodiments for a bonded photonic chip coupler for SOI chip-fiber coupling provide for reduced mismatch between fiber and chip, increased coupling efficiency, and lower photonics device insertion loss. In an embodiment, an optical coupler for coupling a photonics chip to an optical fiber includes a photonic chip comprising a nano-sized photonic waveguide, photonic optical diffraction surface grating, and a first cladding covering the photonic waveguide and the photonic grating; and an optical coupling chip comprising a micron-sized coupling waveguide and a coupling optical diffraction surface grating embedded in a first coupling cladding and on a second coupling cladding, wherein the first coupling cladding is connected to the first cladding, wherein the optical coupling chip is configured to couple to light transmitted between the photonic chip and an optical fiber.