Metal-insulator transition based non-volatile, rewritable, all-optical imprinting on VO₂

All-optical material manipulations are highly desirable in modern telecommunication networks for signal routing and storage, because it can eliminate the need for optical-electrical conversions that hamper data rate and generate extra energy consumptions. We demonstrate the reversible writing and erasing of metallic structures in VO₂ using a single visible laser beam by either varying the environmental pressure or tuning the laser pulse duration. Different from the conventional laser heating based phase-change materials used in optical data storage, the effects observed in VO₂ are driven by photochemical reactions related to the molecules in the air. The laser-patterned structures are stable in the air for days and can be easily read-out through their substantially altered resistance, reflectance, and structural properties and fully compatible with super-resolution optical techniques, these findings provide a new route for non-volatile photonic information processing.