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arXiv · 2207.11193

Synthesizing a $\hat{\sigma}_z$ spin-dependent force for optical, metastable, and ground state trapped-ion qubits

O. Băzăvan·S. Saner·M. Minder·A. C. Hughes·R. T. Sutherland·D. M. Lucas·R. Srinivas·C. J. Ballance
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Abstract

A single bichromatic field near-resonant to a qubit transition is typically used for $\hat{\sigma}_x$ or $\hat{\sigma}_y$ M{\o}lmer-S{\o}rensen type interactions in trapped ion systems. Using this field configuration, it is also possible to synthesize a $\hat{\sigma}_z$ spin-dependent force by merely adjusting the beat-note frequency. Here, we expand on previous work and present a comprehensive theoretical and experimental investigation of this scheme with a laser near-resonant to a quadrupole transition in $^{88}$Sr$^+$. Further, we characterise its robustness to optical phase and qubit frequency offsets, and demonstrate its versatility by entangling optical, metastable, and ground state qubits.

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O. Băzăvan, S. Saner, M. Minder, A. C. Hughes, R. T. Sutherland, D. M. Lucas, R. Srinivas, C. J. Ballance. 2022-07-22. Synthesizing a $\hat{\sigma}_z$ spin-dependent force for optical, metastable, and ground state trapped-ion qubits. https://doi.org/10.1103/physreva.107.022617

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