We repeated the experiment on many different samples and found that overall, the QE of transfer for the in-situ case is always higher than the control case, from > 85% compared to the mixed case of 35-63%. The average experimental QEs of multiple trials are reported in Figure (black data points) along with their standard errors of the mean. For the mixed system, we started at low concentrations of added QDs and found that we were not able to observe energy transfer until we reached the concentrations shown above. Even with this much higher ratio of QD per NPL, we were not able to cross the QE threshold that we observed in the in-situ case. We observed that the QE scales with concentration likely because these QDs experience energy transfer through FRET rather than near-field like the in-situ case (Figure ).