Broadband near-infrared quantum cutting in metal-ion codoped Y ₃Al₅O₁₂ thin films grown by pulsed-laser deposition for solar cell application

We have deposited thin films of yttrium aluminum garnet (YAG) doped with Ce3+ and Yb3+ on quartz and silicon substrates by pulsed laser deposition. Near-infrared (NIR) quantum cutting which involves the emission of NIR photons through the downconversion from Ce3+ to Yb3+ is realized. Upon the broadband excitation of Ce3+ ions with a visible photon at the peak wavelength of 450 nm, NIR photons are generated by Yb3+ ions, with an emission wavelength centered at 1030 nm. The luminescent decay curves of Ce3+ were recorded as a supporting evidence corresponding to the energy transfer. This work offers a better and more convenient approach compatible with crystalline silicon solar cell compared to conventional bulk phosphors.