Experimental enhancement of the photocurrent in a solar cell using upconversion process in fluoroindate glasses exciting at 1480 nm

In this work, the generation of photocurrent in a commercial solar cell has been achieved under excitation at 1480 nm in fluoroindate glass samples codoped with Yb3+ and Er3+ ions. These samples were placed over a solar cell and under excitation at 1.48 µm, upconversion emissions coming from the Yb3+ and Er3+ ions were obtained. In the upconversion emission spectra, several emission bands at 545 nm, 660 nm and 975 nm have been detected for all the analyzed samples (doped with different Yb3+ and Er3+ concentrations). The dependence of the external quantum efficiency to produce photocurrent with the Er3+ and Yb3+ concentration and with the pump power excitation at 1480 nm has been analyzed. As conclusion, the maximum generation of photocurrent was obtained with the highest and lowest concentrations of Er3+ and Yb3+, respectively.