Re:Quantum teleportation over 143 kilometres using active fe...
by stordoff on Sunday September 09, 2012 @04:44PM
(#4496915)
In addition to the transportation benefit, it can be used for computation. The example given in the Coursera course was to suppose that we have a qubit (quantum bit) Y on which we wish to perform some unreliable computation. If it fails, then Y's state is lost. Further suppose that Y is costly (e.g. time consuming) to re-create.
Instead, we can create a pair of entangled qubits (which is easy to do - just a single quantum gate), as one would when teleporting a qubit. We then apply the computation to one of these qubits, and try again with a new pair of qubits if it fails.
Once we have successfully applied the computation, we can teleport our "expensive" qubit Y using this entangled pair. The result is that we now have Y with the computation applied, but there is no risk of losing Y's state.
The details are rather more tricky (only certain computations can be used, some require a correction after teleportation etc.), but this basis can (and has) be built on to develop, for example, fault tolerant quantum computing.
Instead, we can create a pair of entangled qubits (which is easy to do - just a single quantum gate), as one would when teleporting a qubit. We then apply the computation to one of these qubits, and try again with a new pair of qubits if it fails.
Once we have successfully applied the computation, we can teleport our "expensive" qubit Y using this entangled pair. The result is that we now have Y with the computation applied, but there is no risk of losing Y's state.
The details are rather more tricky (only certain computations can be used, some require a correction after teleportation etc.), but this basis can (and has) be built on to develop, for example, fault tolerant quantum computing.