@article {1463672, title = {Photonic Spin Hall Effect in Robust Phase Gradient Metasurfaces Utilizing Transition Metal Nitrides}, journal = {ACS Photonics}, volume = {6}, year = {2018}, pages = {99-106}, author = {K Chaudhuri and A. Shaltout and D Shah and U Guler and Dutta, A and V. M. Shalaev and A. Boltasseva} }