Extending orbital angular momentum multiplexing to radially high orders for massive mode channels in fiber transmission.

Orbital angular momentum (OAM) beams with different angular indices l have the potential to greatly increase communication capacity. However, the finite aperture of optical systems limits the value of the angular index. In order to fully use the orthogonal mode channels supported in the fiber for high-capacity communications, we propose extending the radial indices p of OAM modes as an additional multiplexing dimension.

Performance optimization of multi-plane light conversion (MPLC) mode multiplexer by error tolerance analysis.

The linear polarized (LP) mode multiplexer based on the inverse designed multi-plane light conversion (MPLC) has the advantages of low insertion loss and low mode crosstalk. However, the multiplexer also requires the fabrication and alignment accuracy in experiments, which have not been systematically analyzed. Here, we perform the error tolerance analysis of the MPLC and summarize the design rules for the LP mode multiplexer/demultiplexer.

Ultra-broadband all-dielectric metamaterial thermal emitter for passive radiative cooling.

Passive radiative cooling, which pumps heat to outer space via thermal radiation, has been a promising energy free technology to maintain the earth surface temperature. Nighttime radiative cooling technology is quite mature, while daytime radiative cooling still poses many challenges due to the requirement of minimization of incident solar absorption and maximization of the mid-infrared emissivity in the atmospheric transparency windows. However, the mid-infrared emissivity efficiency of natural materials is usually poor, providing a low cooling efficiency and the realization of a high performance daytime radiative cooler is still quite challenge.