Process tomography of field damping and measurement of fock state lifetimes by quantum nondemolition photon counting in a cavity
       
        
      Physical Review Letters
      101,
        
      
      
        (2008)
          
    
         
    
    
        The relaxation of a quantum field stored in a high-Q superconducting cavity is monitored by nonresonant Rydberg atoms. The field, …
      
    
      
      
      
      
        
  M. Brune, J. Bernu, C. Guerlin, S. Deleglise, C. Sayrin, S. Gleyzes, S. Kuhr, I. Dotsenko, J. M. Raimond, S. Haroche