@article {1059526, title = {Controlling propagation and coupling of waveguide modes using phase-gradient metasurfaces}, journal = {Nature Nanotechnology}, year = {2017}, url = {https://www.nature.com/nnano/journal/vaop/ncurrent/full/nnano.2017.50.html}, author = {Zhaoyi Li and Myoung-Hwan Kim and Wang, Cheng and Zhaohong Han and Sajan Shrestha and Adam Christopher Overvig and Ming Lu and Aaron Stein and Anuradha Murthy Agarwal and Lon{\v c}ar, Marko and Nanfang Yu} }