1 / ω electric-field noise in surface ion traps from correlated adsorbate dynamics

Journal Article · 18 January 2022 · Physical Review A

DOI: https://doi.org/10.1103/physreva.105.013107 · OSTI ID:1861247

Foulon, Benjamin L.  ^[1]; Ray, Keith G. ^[2]; Kim, Chang-Eun ^[2]; Liu, Yuan ^[3]; Rubenstein, Brenda M.  ^[1]; Lordi, Vincenzo  ^[2]

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1. Brown Univ., Providence, RI (United States)
2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
3. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Center for Ultracold Atoms, Research Lab. of Electronics

Ion traps are promising architectures for implementing quantum computers, but they suffer from excessive “anomalous” ion motional heating that limit their overall coherence and practicality for scalable quantum computing. The exact microscopic origins of anomalous heating remain an open question, but experiments point to adsorbates on trap electrodes as one likely source. Many different models of anomalous heating have been proposed, but these models have yet to pinpoint the atomistic origin of the experimentally observed 1/ω electric-field noise scaling seen in ion traps at frequencies between 0.1–10 MHz. In this work, we show that a model based on previously proposed surface-induced dipole fluctuations on adsorbates, but which also incorporates interparticle interaction dynamics through molecular dynamics simulations of up to multiple monolayers of adsorbates, gives rise to 1/ω frequency scaling at the MHz frequencies typically employed in ion traps. Overall, these results demonstrate that moderate-to-high densities of adsorbates can give rise to a set of activated motions that produce the 1/ω noise observed in ion traps and that collective adsorbate motions produce the observed noise spectra that a noninteracting model does not capture.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1861247
• Report Number(s): LLNL-JRNL-821481; 1033232
• Journal Information: Physical Review A, Journal Name: Physical Review A Journal Issue: 1 Vol. 105; ISSN 2469-9926
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English