A strict wave theory of light cannot explain this wavelength threshold, since many long waves should pack the same total energy as a few short waves. Albert Einstein deciphered the mystery in 1905 ...

An international team of researchers demonstrated a technique that allows the laser to electrically switch emission between the long- and short-wavelength edges of the photonic bandgap simply by ...

"However, this light has to be very short-pulsed, so that the material ... "We were the first to use a laser with such a long wavelength for the creation of plasma," says Spielmann.