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| || | || | || | ||  | \| ||  /_   _// |      \\ 
| '--' || | || | ||  |  ' ||   -| ||-  |  --  // 
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|_|| |_||  \____//   |_|\_||  /_____// |______// 
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Text this: Ultrafast all-optical switching in one-dimensional photonic crystal with two defects