Luminescent downconverters operate on the principle of spontaneous emission, where high-energy excitation photons are absorbed, undergo internal relaxation, and are subsequently re-emitted as lower-energy photons. 

In this approach, colloidal quantum dots (QDs) are utilized (Binary blends) as the active luminescent media to achieve sharp spectral tunability and efficient downconversion. However, a major bottleneck in operating downconverters at high efficiencies is heat generation under intense optical pumping and thermal relaxation, which requires careful thermal management to prevent degradation and thermal quenching.