Near infrared quantum cutting in heavy Yb doped Ce0.03Yb3xY(2.97-3x)Al5O12 transparent ceramics for crystalline silicon solar cells

Near infrared (NIR) quantum cutting involving the conversion of an absorbed blue photon into two NIR photons emission has been realized in heavy Yb doped Ce0.03Yb3xY(2.97-3x)Al5O12 (x=0.1, 0.25, and 0.5) transparent ceramics. Upon the 467 nm excitation, the energy transfer process was dominated by the cooperative downconversion from the 5d1 state of one Ce3+ ion to the 2F5/2 state of two Yb3+ ions. The influence of the Ce4+-Yb2+ charge transfer state (CTS) should not contribute much to the energy transfer process for the large energy gap between Ce3+:5d1 and the CTS. The calculated quantum yield of Yb3+ for the x=0.25 sample without concentration quenching was 175.4%.