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Transport quantum logic gates for trapped ions



Dietrich G. Leibfried, Emanuel H. Knill, Christian Ospelkaus, David J. Wineland


Many efforts are currently underway to build a device capable of large scale quantum information processing (QIP). While QIP has been demonstrated for a few qubits in several systems, severe difficulties have to be overcome in order to construct a large scale device. In one proposal for large- scale QIP, trapped ions are manipulated by precisely controlled light pulses and moved through and stored in multi-zone trap arrays. The technical overhead necessary to precisely control both the ion motion and the laser interactions is demanding. Here we propose methods to significantly reduce the overhead on laser beam control for performing single and multiple qubit operations on trapped ions. We show how a universal set of operations can be implemented by controlled transport of ions through stationary laser beams. At the same time, each laser beam can be used to perform many operations in parallel, potentially reducing the total light power necessary to carry out a certain QIP task. The overall setup necessary for implementing transport gates is simpler than for gates executed on stationary ions. We also suggest a transport-based two-qubit gate scheme utilizing micro-fabricated permanent magnets that can be executed without laser light.
Physical Review A (Atomic, Molecular and Optical Physics)


quantum logic, scalability, transport gate, trapped ions


Leibfried, D. , Knill, E. , Ospelkaus, C. and Wineland, D. (2007), Transport quantum logic gates for trapped ions, Physical Review A (Atomic, Molecular and Optical Physics), [online], (Accessed May 26, 2024)


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Created September 21, 2007, Updated January 27, 2020