Abstract
Off-resonant excitation: For shorter gate pulses errors due to off-resonant excitation increase. The sharp edges of the pulse have a broad frequency spectrum. These different frequency components can drive the second motional mode, higher orders and counter-rotating modes of the main motional mode and will cause an AC Stark shift coupling to the carrier depending on the un-stabilised relative phase of the Raman beams \(\phi _0\). Shaping the edge of the pulse on the timescale of a few motional periods of the ion’s motion reduces the pulse bandwidth and strongly suppresses errors due to off-resonant excitation [1]. However this method starts to fail once the total gate length is on the same order of magnitude as the ideal pulse shaping length.
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Notes
- 1.
Note the difference between \(\phi _0\), the initial relative phase of the Raman lasers and \(\varphi _0\), used for various other phase offsets.
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Schäfer, V.M. (2020). Fast Gates. In: Fast Gates and Mixed-Species Entanglement with Trapped Ions. Springer Theses. Springer, Cham. https://doi.org/10.1007/978-3-030-40285-3_7
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DOI: https://doi.org/10.1007/978-3-030-40285-3_7
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