I am particularly interested where it says:
"...By sandwiching a thin layer of the lead halide perovskite between two mirrors, the team produced an optically driven laser which proves these cells "show very efficient luminescence" - with up to 70% of absorbed light re-emitted.
Because this has given me an idea; one thing that makes it difficult to design a solar cell to be very efficient is that natural light consists of a wide range of wavelengths and it is extremely difficult to design a solar cell to efficiently convert ALL those wavelengths into electricity. Now,I take it this laser can efficiently convert most of those wavelengths into one frequency of light or at least it is possible to make such a laser that can? if so, why not make a solar cell that works by using such lasers on its surface to convert all those frequencies of laser light to just one frequency and then, lower down below the surface, have separate structures fine-tuned to efficiently convert just that one frequency of laser light to electrical energy? By doing that, it should be a lot easier and simpler to design the solar cell extremely energy efficient? -just an idea.