Yu Guo

Two simultaneous interpreters sit in the same booth. The first translates from English into Russian but swallows half the words. The second goes from Russian into French, and also loses half. If you put them together, you'd expect a mess: the losses would add up, and only a quarter of the meaning would reach the listener. But what if they start correcting each other?

In an ordinary semiconductor, it is hard to get two things at once: strong magnetism and a tightly bound electron-hole pair that is born when light is absorbed. Magnetic impurities, which make a material magnetic, also prevent the electron and hole from staying together: they are like noisy neighbors that do not let the pair exist in peace.