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Trapped-Ion Quantum Logic Utilizing Position-Dependent ac Stark Shifts

Peter Staanum·Michael Drewsen
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Abstract

We present a scheme utilizing position-dependent ac Stark shifts for doing quantum logic with trapped ions. By a proper choice of direction, position and size, as well as power and frequency of a far-off-resonant Gaussian laser beam, specific ac Stark shifts can be assigned to the individual ions, making them distinguishable in frequency-space. In contrast to previous all-optical based quantum gates with trapped ions, the present scheme enables individual addressing of single ions and selective addressing of any pair of ions for two-ion quantum gates, without using tightly focused laser beams. Furthermore, the decoherence rate due to off-resonant excitations can be made negligible as compared with other sources of decoherence.

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Peter Staanum, Michael Drewsen. 2002-06-19. Trapped-Ion Quantum Logic Utilizing Position-Dependent ac Stark Shifts. https://doi.org/10.1103/physreva.66.040302

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