Noise is usually undesired yet inevitable in science and engineering. However, by introducing the engineered noise to the precise solution of Jones matrix elements, the research groups of Prof. Ruwen Peng (彭茹雯) and Prof. Mu Wang (王牧) from the School of Physics, Nanjing University, together with the group of Prof. Yongmin Liu from Northeastern University, USA, break the fundamental limit of polarization multiplexing capacity of metasurfaces. This limitation roots from the dimension constraints of the Jones matrix, leading to the independent channels of polarization multiplexing no more than three. The researchers developed an approach based on noise engineering that breaks this fundamental limit. By introducing the correlated noise with least squares estimation, new polarization channels could be created with only moderate cross-talk. To reduce the cross-talk, they further introduced the noncorrelated noise with a random distribution to push the limit of polarization multiplexing. Eventually, they experimentally realized up to 11 independent holographic images using a single metasurface illuminated by visible light with different polarizations. This is the highest capacity reported so far for polarization multiplexing. Combining the position multiplexing scheme, they achieved 36 distinct images with the metasurface, forming a holographic keyboard pattern. This discovery implies a new paradigm for high-capacity optical display, information encryption, and data storage.
For detailed information, please read the recent research article in Science titled “Breaking the limitation of polarization multiplexing in optical metasurfaces with engineered noise,” Science 379, 294-299 (2023),https://www.science.org/stoken/author-tokens/ST-979/full.
Fig.1 Breaking the limitation of polarization multiplexing in optical metasurfaces with engineered noise.