I found the following abstract interesting because the colors emitted by this long lasting phosphorescence (blue, green, and red) are exactly the colors I have seen displayed by these flying craft, along with white light, which can produced by combining blue, green, and red light.
In this experiment we can see that the effect of doping is to create long lasting phosphorescence which means that we have created a type of 'storage battery', since the material is both a collector and is also the battery (an elegant and obvious solution) but at the same time we can see that the battery, while an improvement, continues to 'leak'. It is at this point that we would want to begin to experiment with magnets, since intuition suggests that it is the magnet that both prevents leakage, and then is also employed to liberate electrons, not as photons, but rather as a useful electric current.
Femtosecond laser-induced three-dimensional bright and long-lasting phosphorescence inside calcium aluminosilicate glasses doped with rare earth ions We report on a novel phenomenon in calcium aluminosilicate glasses doped with Ce3 + , Tb3 + , and Pr3 + . After irradiation by an 800 nm femtosecond pulsed laser, the focused part of the laser in the glasses emits bright and long-lasting phosphorescence able to be clearly seen with the naked eye in the dark even one hour after the removal of the activating laser. Moreover, by selecting appropriate glass compositions and species of rare earth ions, optional three-dimensional image patterns emitting long-lasting phosphorescence in various colors, including blue, green, and red, can be formed within glass samples by moving the focal point of the laser. Based on absorption spectra, the long-lasting phosphorescence is considered to be due to the thermostimulated recombination of holes and electrons at traps induced by the laser irradiation, which leave holes or electrons in a metastable excited state at room temperature. ©1998 American Institute of Physics.