Measurement of Optical Constants of TiN and TiN/Ti/TiN Multilayer Films for Microwave Kinetic Inductance Photon-Number-Resolving Detectors. - Dai, M.; Guo, W.; Liu, X.; Zhang, M.; Wang, Y.; Wei, L. F.; Hilton, G. C.; Hubmayr, J.; Ullom, J.; Gao, J.; Vissers, M. R. (Journal of Low Temperature Physics, 2019)