A Cryogenic Penning Trap Based on Permanent Magnets

F. Völksen; K. K. Anjum; R. P. Czampiel; N. Daehnhardt; S. Gavranovic; J. Hoentges; L. Kürschner; J. D. Regier; D. Schweitzer; 1; 2; P. Schöps; A. M. Thomas; S. Wienhues; B. Arndt; T. Imamura; S. Endoh; B. M. Latacz; M. Leonhardt; P. Micke; J. Morgner; D. Natakala; S. Stahl; H. Yildiz; K. Blaum; J. A. Devlin; Y. Matsuda; C. Ospelkaus; W. Quint; A. Soter; J. Walz; C. Smorra; S. Ulmer

arXiv · 2609.26858

A Cryogenic Penning Trap Based on Permanent Magnets

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Abstract

We report on a Penning trap based on NdFeB permanent magnets operated at 4\,K with a magnetic field strength of 280\,mT. Reliable loading and confinement of protons, H$_2^+$ ions, and electrons was demonstrated with non-destructive single-particle detection sensitivity of protons and H$_2^+$ ions using superconducting image-current circuits. The axial frequency of individual particles reaches a shot-to-shot stability of 47 parts-per-billion comparable to that of state-of-the-art precision Penning-trap experiments. Measurements of the proton modified-cyclotron frequency show a shot-to-shot scatter of $0.14$ parts per million (p.p.m.), presently limited by millikelvin-level temperature fluctuations of the permanent-magnet assembly. We outline a route towards improving this performance by more than an order of magnitude. This development offers broad potential for axial-mode-related precision measurements and cost-efficient Penning-trap experiments, and represents an important step towards compact, scalable, and transportable antiproton-trap systems.

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F. Völksen, K. K. Anjum, R. P. Czampiel, N. Daehnhardt, S. Gavranovic, J. Hoentges, L. Kürschner, J. D. Regier, D. Schweitzer, 1, 2, P. Schöps, A. M. Thomas, S. Wienhues, B. Arndt, T. Imamura, S. Endoh, B. M. Latacz, M. Leonhardt, P. Micke, J. Morgner, D. Natakala, S. Stahl, H. Yildiz, K. Blaum, J. A. Devlin, Y. Matsuda, C. Ospelkaus, W. Quint, A. Soter, J. Walz, C. Smorra, S. Ulmer. 2026-09-22. A Cryogenic Penning Trap Based on Permanent Magnets. https://arxiv.org/abs/2609.26858

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