Efficient sympathetic motional ground-state cooling of a molecular ion

Abstract

Cold molecular ions are promising candidates in various fields ranging from precision spectroscopy and test of fundamental physics to ultra-cold chemistry. Control of internal and external degrees of freedom is a prerequisite for many of these applications. Motional ground state cooling represents the starting point for quantum logic-assisted internal state preparation, detection, and spectroscopy protocols. Robust and fast cooling is crucial to maximize the fraction of time available for the actual experiment. We optimize the cooling rate of ground state cooling schemes for single ${}^{25}{\mathrm{Mg}}^{+}$ ions and sympathetic ground state cooling of ${}^{24}{\mathrm{MgH}}^{+}$. In particular, we show that robust cooling is achieved by combining pulsed Raman sideband cooling with continuous quench cooling. Furthermore, we experimentally demonstrate an efficient strategy for ground state cooling outside the Lamb-Dicke regime.

11 pages, 11 figures

References in corpus (10)

• Sideband Cooling Micromechanical Motion to the Quantum Ground State
• Quantum computing with trapped ions
• Resolved Sideband Cooling of a Micromechanical Oscillator
• 'Designer atoms' for quantum metrology
• Enhanced sensitivity to variation of the fine structure constant and m_p/m_e in diatomic molecules
• Progress toward a first observation of parity violation in chiral molecules by high-resolution laser spectroscopy
• Candidate molecular ions for an electron electric dipole moment experiment
• Probing isotope effects in chemical reactions using single ions
• Challenges of laser-cooling molecular ions
• Memory coherence of a sympathetically cooled trapped-ion qubit

Cited by in corpus (6)

• Sympathetic ground state cooling and time-dilation shifts in an ${}^{27}{\text{Al}}^{+}$ optical clock
• Quantum control of molecules for fundamental physics
• Unexpectedly large difference of the electron density at the nucleus in the 4p ${}^2$P${}_{1/2,3/2}$ fine-structure doublet of Ca${}^{+}$
• Optimized pulsed sideband cooling and enhanced thermometry of trapped ions
• Vibronic spectroscopy of sympathetically cooled CaH${}^{+}$
• Adiabatic Sensing Technique for Optimal Temperature Estimation using Trapped Ions