Perspectives on Designer Photocathodes for X-ray Free-Electron Lasers: Influencing Emission Properties with Heterostructures and Nanoengineered Electronic States

Nathan A. Moody, Kevin L. Jensen, Andrew Shabaev, Samuel G. Lambrakos, John Smedley, Daniel Finkenstadt, Jeffrey M. Pietryga, Petr M. Anisimov, Vitaly Pavlenko, Enrique R. Batista, John W. Lewellen, Fangze Liu, Gautam Gupta, Aditya Mohite, Hisato Yamaguchi, Mark A. Hoffbauer, István Robel