In future military operations, aircraft and submarines may be
able to stay in contact by firing up the laser comm. Researchers
have devised a new way to communicate with submarines by using
high-energy laser beams to create bubbles of steam in the water,
which then pop in little explosions that generate a 220-decibel
pulse of sound. By controlling the frequency of explosions,
researchers could make a kind of underwater Morse code.
According to a press release from the U.S. Naval Research
Laboratory, one of the peculiar effects of high-intensity laser
beams is that they can actually focus themselves when passing
through some materials, like water. As the laser focuses, it
rips electrons off water molecules, which then become
superheated and create a powerful “pop”. Because different
colours of light travel at markedly different speeds underwater,
the precise location where different colours focus together
could be manipulated by the suitable design of a many-coloured
input pulse [BBC News]. Researchers also no