Researchers have developed a new method of building programmable integrated switching units on silicon photonic chips by implanting germanium ions that can alter the chip's refractive index and be erased using laser annealing. This allows a generic optical circuit to be fabricated and later programmed for specific applications like LiDAR, reducing production costs and enabling wider adoption. The researchers demonstrated reconfigurable waveguides and switches for applications like biochemical sensing and high-performance computing.