Register for free to
view the full innovation profile.
A design for a quantum logical gate between single photons (specifically, a conditional phase gate) with the following properties
About
We present a design for a quantum logical gate between single photons (specifically, a conditional phase gate) with the following properties: * It is deterministic in principle (photon losses would make it probabilistic, but the failure probability can be reduced exponentially fast by adopting a redundant strategy).
Key Benefits
* Photons are excellent carriers of quantum information, requiring only optical fibers to travel, and single-photon logical operations are trivial, which is why photons have the field to themselves in, for instance, quantum cryptography applications. Our invention would add substantially to these already well-known advantages, by essentially removing the photons‚ only weakness. * The ability to engineer logical gates between photons would make it possible, for instance, to build efficient quantum repeaters, thereby greatly extending the range of existing quantum communication networks. Individual photons are also cheap to produce and carry very little energy, so a photonic quantum computer consisting entirely of passive gates could run at extremely high clock speeds and require very little power to operate.
Applications
Application(s): A conditional phase gate between photons can be used to, essentially, build a single-photon photonic transistor, which could be used for single-photon switches and routers. It can also be used to carry out a complete, deterministic Bell-state measurement on a photon pair. This has applications to the deterministic generation of entangled states, with potential uses in quantum cryptography and to build quantum repeaters; devices relying on quantum teleportation; and, of course, quantum computers.