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arXiv · 2004.05190

Efficient ground-state cooling of large trapped-ion chains with an EIT tripod scheme

L. Feng·W. L. Tan·A. De·A. Menon·A. Chu·G. Pagano·C. Monroe
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Abstract

We report the electromagnetically-induced-transparency (EIT) cooling of a large trapped $^{171}$Yb$^+$ ion chain to the quantum ground state. Unlike conventional EIT cooling, we engage a four-level tripod structure and achieve fast sub-Doppler cooling over all motional modes. We observe simultaneous ground-state cooling across the complete transverse mode spectrum of up to $40$ ions, occupying a bandwidth of over $3$ MHz. The cooling time is observed to be less than $300\,\mu$s, independent of the number of ions. Such efficient cooling across the entire spectrum is essential for high-fidelity quantum operations using trapped ion crystals for quantum simulators or quantum computers.

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L. Feng, W. L. Tan, A. De, A. Menon, A. Chu, G. Pagano, C. Monroe. 2020-04-10. Efficient ground-state cooling of large trapped-ion chains with an EIT tripod scheme. https://doi.org/10.1103/physrevlett.125.053001

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