Rotation Sensing with Trapped Ions

We report on work towards realizing a precision rotation sensor with a single trapped $^{138}{\rm Ba}^+$ ion [1], building on the recently-developed technique of spin-dependent kicks (SDKs) [2,3] with a novel scheme based on a Zeeman qubit. We have demonstrated single-qubit manipulations in the ground state manifold of $^{138}{\rm Ba}^+$, using a picosecond pulsed laser to drive Raman transitions, 44~THz detuned, with Rabi frequencies up to ${\sim}100$~kHz. We also report on recent progress on using the same system to effect spin-motion entanglement. Demonstrating such entanglement will quickly enable free-oscillation interferometry with ultracold trapped ions. Anticipated rotation sensing precision will be competitive with commercial rotation sensors. Implementation of SDKs with Zeeman levels in $^{138}$Ba may also provide a versatile technique of achieving large momentum transfer that could be broadly applicable to matter-wave interferometery.\\ \\References: \\ \\ $[1]$W. C. Campbell and P. Hamilton, J. Phys. B 50, 064002 (2017)\newline \\$[2]$J. Mizrahi et al., Phys. Rev. Lett. 110, 203001 (2013)\newline \\$[3]$Jaffe et al., Phys. Rev. Lett. 121, 040402 (2018)