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yocto-Newton force detection sensitivity using trapped ions



Michael J. Biercuk, Joseph W. Britton, Hermann Uys, Aaron Vandevender, John Bollinger


Recent experimental advances have shown that it is possible to detect forces arising from electric fields at a level of aN/ √Hz (atto = 10-18 through coupling of micro or nanofabricated mechanical resonators to a variety of physical systems including single-electron transistors, superconducting microwave cavities, and individual spins. These experiments have allowed for probing studies of the physics of quantum-mechanical backaction and for the development of a new technology base founded on the capability of detecting extremely small external forces. In a host of formats trapped atomic ions have been proposed as ideal candidates for the detection of small forces, including applications in materials science. Using small crystals of 9Be+ in a Penning trap, we demonstrate detection of forces as small as 174 yN (yocto = 10-24) using a crystal of 60 ions. Force detection sensitivity using this crystal is calculated to be 390+/-150 yN/ √Hz using phase-sensitive detection of an externally applied electric field, and we extract a normalized force detection sensitivity of 50+/-20 yN/ √Hz for n = 1. This result is approximately four orders of magnitude better than previous reports of sensitive force detection due to the small mass of harmonically confined trapped-ion resonators. This technique is based on the excitation of normal motional modes in an ion trap and phase-coherent Doppler velocimetry, which allows for the discrimination of ion motion with amplitudes on the scale of nanometers, and represents a significant advancement in the precision measurement of small forces.
Nature Physics


Doppler velocimetry, force sensitivity, ion traps, laser cooling, Penning trap, yocto-Newton


Biercuk, M. , Britton, J. , Uys, H. , Vandevender, A. and Bollinger, J. (2010), yocto-Newton force detection sensitivity using trapped ions, Nature Physics, [online], (Accessed April 12, 2024)
Created August 21, 2010, Updated October 12, 2021