In the recently published ACS Photonics paper titled "Time Reversal Differentiation of FDTD for Photonic Inverse Design", co-first authors Jerry Tang Rui Jie and Soon Wei Daniel Lim present a novel approach for computing gradients in finite difference time domain (FDTD) simulations for photonic inverse design. Their technique surmounts the memory constraints inherent in automatic differentiation (AD) and preserves the computational efficiency of the state-of-the-art adjoint method. The method calculates gradients by replaying time-dependent fields at lossy boundaries, which significantly...