In quantum computing, the SWAP gate is a two-qubit quantum logic gate that swaps the states of two qubits.
Operation
editThe SWAP gate operates on a quantum register of two qubits. The SWAP gates swaps the states of the two qubits. For example, on the computational basis states , , , and :
- SWAP =
- SWAP =
- SWAP =
- SWAP =
In permutation matrix form, the SWAP gate is represented by the 4x4 unitary matrix:
- .
Hence, on a more general arbitrary superposition ,
- SWAP
See also
editNotes
editReferences
edit- Nielsen, Michael A.; Chuang, Isaac (2000). Quantum Computation and Quantum Information. Cambridge: Cambridge University Press. ISBN 0521632358. OCLC 43641333.