Silicon once was said to have speed limitations. Therefore much research was conducted on (and some rather secret ICs have been created using) Gallium Nitrate, Silicon Nitrate, and Gallium Phospherous technologies. Also repeatedly experimented with were 'Silicon on Saffire' and Diamond based semiconductors. Speeds necessary to switch light will be necessary to maintain Moore's law.
Details here are sketchy and I have not read any of this in industry publications. Don't know if this will really be the breakthrough technology equivalent to a world's first transistor. However, potential here is so significant that I am posting this heads up:
Intel Reports a Research Leap to a Faster Chip
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