Scientists discovered a way to create LEDs that can also detect and absorb light. They modified tiny versions of LEDs, called quantum dots, and created nanorods in which quantum dots directly contact two semiconductor materials. One allows movement of positive charge, and the other the negative one

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Scientists discovered a way to create LEDs that can also detect and absorb light. They modified tiny versions of LEDs, called quantum dots, and created nanorods in which quantum dots directly contact two semiconductor materials. One allows movement of positive charge, and the other the negative one