Quantum Rainbow Photon Gun Unveiled We’ve heard much about the
possibility of a quantum internet which uses single photons to
encode and send information protected by the emerging technology
of quantum cryptography. The main advantage is of such a system
is perfect security, the kind of thing that governments, the
military, banks and assorted other groups would pay handsomely
to achieve. One of the enabling technologies for a quantum
internet is a reliable photon gun that can fire single photons
on demand. That’s not easy. One of the significant weaknesses of
current quantum cryptographic systems is the finite possibility
that today’s lasers emit photons in bunches rather than one at a
time. When this happens, an eavesdropper can use these extra
photons to extract information about the data being transmitted.
So there’s no shortage of interest in developing photon guns
that emit single photons and indeed various groups have made
significant progress towards this. Against this background,
Michael Fortsch at th