text: 1 
  ) 
  
  ∞ 
  W 
  ( 
  
  / 
  ) 
  c 
  0.5 
  ω 
  W 
  ( 
  
  Dirty Limit 
  Clean Limit 
  
  0.5 
   in eV 
  ω 
  c 
  
  Superconducting State Optical Sum (BCSI) 
  
  1 
  ) 
  
  ∞ 
  W 
  ( 
  
  / 
  ) 
  c 
  0.5 
  ω 
  W 
  Dirty Limit 
  Clean Limit 
  
  ( 
  
  0 
  0 
  0.5 
   in eV 
  1 
  ω 
  c 