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So, I assume that the problem has not been to find a material which is capable of emitting blue light, but rather to be able to extract blue light out of that material reliably.
This explanation is valuable in a sense that I have used my own knowledge without referring to external material, but of course it falls short on explaining what do I actually mean by the terms I have used such as “material” or “reliable” academically. So indeed, I have to provide exact definitions as reliable sources for what I am going to present.
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