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

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Text this: Optical studies of topological insulator Bi1:5 Sb0:5 Te1:8 Se1:2 using terahertz time-domain spectroscopy.