Coherently manipulating two-qubit quantum information using a pair of simultaneous laser pulsesL. F. Wei1, 2 and F. Nori1, 3
1 Frontier Research System, The Institute of Physical and Chemical Research (RIKEN) - Wako-shi, Saitama, 351-0198, Japan
2 Institute of Quantum Optics and Quantum Information, Department of Physics Shanghai Jiaotong University - Shanghai 200030, PRC
3 Center for Theoretical Physics, Physics Department Center for the Study of Complex Systems, The University of Michigan Ann Arbor, MI 48109-1120, USA
(Received 6 May 2003; accepted in final form 28 October 2003)
Several sequential operations are usually needed for implementing controlled quantum gates and generating entanglement between a pair of quantum bits. Based on the conditional quantum dynamics for a two-ion system beyond the Lamb-Dicke limit, here we propose a theoretical scheme for manipulating two-qubit quantum information, i.e., implementing a universal two-qubit quantum gate and generating a two-qubit entangled state, by using a pair of simultaneous laser pulses. Neither the Lamb-Dicke approximation nor the auxiliary atomic level are required. The experimental realizability of this simple approach is also discussed.
03.67.Lx - Quantum computation.
32.80.Pj - Optical cooling of atoms; trapping.
© EDP Sciences 2004