Spectral Properties of Cs and Ba on Cu(111) at Very Low Coverage: Two-photon Photoemission Spectroscopy and Electronic Structure Theory
  
  
    
  
  
  
  
  
    
    
            S. Achilli𝟙, 
            M. I. Trioni, 
            E. V. Chulkov, 
            P. M. Echenique, 
            V. Sametoglu, 
            N. Pontius, 
            A. Winkelmann, 
            A. Kubo, 
            J. Zhao, 
            H. Petek
  
  
  
  
  
    
    
      
    
    December 2009