Photonic integrated circuits (PICs) have the potential to drastically expand the capabilities of optical information science and engineering. However, PICs are commonly fabricated using selective material etching, a subtractive process. Thus, the chip’s functionality cannot be substantially altered once fabricated. Here, we propose to exploit wide-bandgap non-volatile phase-change materials (PCMs) to create a rewritable PIC platform. A PCM-based PIC can be written using a nano-second pulsed laser, akin to rewritable compact disks. The whole circuit can then be erased by heating, and a completely new circuit can be rewritten. We numerically designed a dielectric-assisted PCM waveguide consisting of a thick dielectric layer on top of a thin layer of wide-bandgap PCMs. The low-loss PCMs and our engineered waveguiding structure lead to negligible optical loss. Furthermore, we analyzed the spatio-temporal laser pulse shape to write the PCMs. Finally, we experimentally demonstrated such a rewritable PIC. Our proposed platform will enable low-cost manufacturing and have a far-reaching impact on the rapid prototyping of PICs, validation of new designs, and photonic education.
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