Entangling photons with electricity
Jun 5, 2010
Researchers in Cambridge in the UK have succeeded in generating entangled photons using electricity alone, with a new device called an "entangled light-emitted diode" (ELED). The device converts electrical current directly into entangled light rather than relying on laser power as in previous technology. The technique could be a practical way to integrate many entangled light sources together on a single chip – something that will be crucial for making a real-world optical quantum computer.
High fidelity photons
The device emits individual entangled pairs of photons when a pulsed current is applied and has an "entanglement fidelity" of 0.82 – a figure that is high enough for it to be used in quantum relays, which are related to core components of quantum computing such as teleportation). Entanglement fidelity is a measure of how pure the entangled light is: if the value exceeds 0.5, light is entangled, with 1 being the maximum value.