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| \  / ||  \ \\/ //  |__  //    / _ \\   /_____// 
|  \/  ||   \ ` //     / //    / //\ \\  `____ `  
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`-`  `-`     `-`'    `-----`  `-`   `-`  /_//     
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Text this: Green electroluminescence from an n-ZnO: Er/p-Si heterostructured light-emitting diode