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What are Quantum Dots?

Quantum dots are semiconductor nanocrystals that are so small they areconsidered dimensionless.

Quantum dots range from 2-10 nanometers (10-50 atoms) in diameter.

Quick e!ie" of #emiconductors

$ semiconductor is a material that has a small %and ga& %et"een the !alence andconduction %and.

$n e'citon &air is defined as an electron and the hole that it lea!es%ehind "hen it is e'cited u& to the conduction %and.

$n e'citon %ohr radius is the distance in an electron-hole &air.

$ Quantum Dot is a semiconductor so small that the sie of the crystal is on thesame order as the sie of the e'citon %ohr radius.

his uni*ue sie &ro&erty causes the +%and, of energies to turn intodiscrete energy le!els.

$rtificial $toms?

Quantum Dots are more closely related to atoms than a %ulk material %ecause oftheir discrete *uantied energy le!els.

hey ha!e %een nicknamed $rtificial $toms.

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'citon /ohr adius he /and a&

/and a&s and therefore the energy associated "ith them de&end on therelationshi& %et"een the sie of the crystal and the e'citon %ohr radius.

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