intermittent noise

Blinking colloidal nanocrystals, also known as 'Quantum Dot Blinking', is a phenomenon observed during studies of single colloidal nanocrystals that show that they randomly turn their photoluminescence on and off even under continuous light illumination.
This has also been described as luminescence intermittency.
Similar behavior has been observed in crystals made of other materials. For example, porous silicon also exhibits this affect.

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