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  _____     _____     _  __     ___     _____    
 |__  //   |  ___||  | |/ //   / _ \\  |  __ \\  
   / //    | ||__    | ' //   | / \ || | |  \ || 
  / //__   | ||__    | . \\   | \_/ || | |__/ || 
 /_____||  |_____||  |_|\_\\   \___//  |_____//  
 `-----`   `-----`   `-` --`   `---`    -----`

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Text this: Azo-dye-doped absorbing photonic crystals with purely imaginary refractive index contrast and all-optically switchable diffraction properties