Laser writing of spin defects in polymers.

Technologies based on quantum effects of spin defects, such as computation, communication, sensing, and anticounterfeiting, have developed rapidly. However, limited by specific crystal structure required for spin defects, wide extension of their application faces challenges. A notable challenge is fabricating spin defects in general-purpose, low-cost amorphous materials such as polymers. Here, we propose an in situ laser-induced fabrication strategy of spin defects from polymers based on manipulation of main and side chains of polymers (MMSCP). By using 17 laser parameters and 8 polymers, we successfully fabricated silicon carbide spin defects derived from material mismatches. ODMR contrast and linewidth are consistently above 0.15% and below 54 megahertz, respectively. Benefiting from minimal damage of laser direct writing and stable covalent bonding, MMSCP effectively fabricates spin defects in manufactured microfluidic devices, cardiac patches, and medicine bottles and applies them to sensing and anticounterfeiting. Overall, MMSCP represents a paradigm that revolutionizes the application scheme of spin defects.