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arXiv · 2208.05332

Measurement-based ground state cooling of a trapped ion oscillator

Chungsun Lee·Simon C. Webster·Jacopo Mosca Toba·Ollie Corfield·George Porter·Richard C. Thompson
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Abstract

Measurement-based cooling is a method by which a quantum system, initially in a thermal state, can be prepared in its ground state through some sort of measurement. This is done by making a measurement that heralds the system being in the desired state. Here we demonstrate the application of a measurement-based cooling technique to a trapped atomic ion. The ion is pre-cooled by Doppler laser cooling to a thermal state with a mean excitation of $\bar n \approx 18$ and the measurement-based cooling technique selects those occasions when the ion happens to be in the motional ground state. The fidelity of the heralding process is greater than 95%. This technique can be applied to other systems that are not as amenable to laser cooling as trapped ions.

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Chungsun Lee, Simon C. Webster, Jacopo Mosca Toba, Ollie Corfield, George Porter, Richard C. Thompson. 2022-08-10. Measurement-based ground state cooling of a trapped ion oscillator. https://doi.org/10.1103/physreva.107.033107

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