Patent ID: 7981667

Claim:
A concentration-gradient quantum dot comprising an alloy of a first semiconductor and a second semiconductor, wherein the concentration of the first semiconductor gradually increases from the core of the quantum dot to the surface of the quantum dot and the concentration of the second semiconductor gradually decreases from the core of the quantum dot to the surface of the quantum dot, wherein the alloy comprises CdSeTe and has a molecular formula CdSe 1-x Te x , the alloy comprises CdSSe and has a molecular formula CdS 1-x Se x , the alloy comprises CdSTe and has a molecular formula CdS 1-x Te x , the alloy comprises ZnSeTe and has a molecular formula ZnSe 1-x Te x , the alloy comprises ZnCdTe and has a molecular formula Zn 1-x Cd x Te, the alloy comprises CdHgS and has a molecular formula Cd 1-x Hg x S, the alloy comprises HgCdTe and has a molecular formula HgCdTe, the alloy comprises InGaAs and has a molecular formula InGaAs, the alloy comprises GaAlAs and has a molecular formula GaAlAs, or the alloy comprises InGaN and has a molecular formula InGaN, wherein x is any fraction between 0 and 1, and wherein the concentration-gradient quantum dot has a band gap energy that is non-linearly related to the molar ratio of the at least two semiconductors.