Recently, there has been great interest in photonic inverse design with the goal of creating groundbreaking photonic devices. This has largely been enabled by the adjoint method, which allows for efficient optimization of electromagnetic structures with respect to a large number of degrees of freedom. However, despite considerable progress, inverse design of large-scale 3D structures using full-wave simulations still requires computational time that can be prohibitively long. Here, we demonstrate photonic inverse design enhanced by a hardware-accelerated finite-difference time-domain solver and automatic differentiation. A large-area, CMOS-compatible grating coupler was optimized in a few hours using our methodology.
|