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Multicolor carbon dot (CD)‐based nanomaterials offer a variety of opportunities for potential applications in bioimaging, optoelectronic devices, and information security. However, it still remains a challenge to modulate the conjugated π‐structure of CDs to achieve multicolor room‐temperature phosphorescence (RTP). Herein, the authors present a strategy based on thermally driven amorphous−crystalline phase transition to achieve multicolor carbonized polymer dots (CPDs) with the emission color tunable from green to orange‐red. This is the first report on multicolor RTP emission from CDs by means of thermal stimulus. Further investigations reveal that the formation of self‐protective covalently crosslinked frameworks and codoping of multiple heteroatoms play a crucial role in the production of RTP. RTP color tunability can be attributed to different crystalline contents of the conjugated π‐domain within CPDs. Potential application of the developed CPDs as printable and writable security inks for advanced multilevel anti‐counterfeiting and encryption is demonstrated. This work paves a path for the development of multicolor RTP materials and suggests great potential of CDs in exploiting novel optical materials toward intriguing applications. [ABSTRACT FROM AUTHOR]

Metasurfaces become an effective route to the control of not only free‐space waves but also surface plasmon polaritons (SPPs). SPPs, propagating along the interface between a metal and a dielectric, show properties of strong enhancement of the local field. Thanks to these essential functionalities, manipulating SPPs in metasurfaces is of particular interest in current research. Here, observation of anomalous SPP propagation is presented when SPPs traverse an interface between two metasurfaces whose topologies of eigenmode equal‐frequency contours are different. By combining various complementary meta‐resonators, SPP propagation was ready to be redirected at the topological transition interface at will. The proposed integrated metasurfaces open unprecedented avenues for anomalous wave propagation and guidance, showing exceptional capabilities for designing photonic devices. [ABSTRACT FROM AUTHOR]