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Demonstration of a Fundamental Universal Quantum Logic Gate



C Monroe, D M. Meekhof, B E. King, Wayne M. Itano, David J. Wineland


We demonstrate the operation of a two-bit "controlled-NOT" quantum logic gate, which, in conjunction with simple single-bit operations, forms a universal quantum logic gate for quantum computation. The two quantum bits are stored in the internal and external degrees of freedom of a single trapped atom, which is first laser cooled to the zero-point energy. Decoherence effects are identified for the operation, and the possibility of extending the system to more qubits appears promising.
Physical Review Letters


Monroe, C. , Meekhof, D. , King, B. , Itano, W. and Wineland, D. (1995), Demonstration of a Fundamental Universal Quantum Logic Gate, Physical Review Letters, [online], (Accessed June 25, 2024)


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Created December 31, 1994, Updated October 12, 2021