Constraining Yukawa-type interaction and coupling constant of axionlike particles to nucleons from recent measurement of the Casimir-Polder interaction

TL;DR

This study exploits a high-precision Casimir-Polder diffraction experiment with Ar atoms on a Si$_3$N$_4$ nanograting to constrain hypothetical short-range forces. By modeling the measured Casimir-Polder interaction with Lifshitz theory and bounding possible contributions from a Yukawa-type potential and from two-axion exchange between nucleons, the authors derive competitive limits on both the Yukawa strength $\alpha$ (as a function of range $\lambda$) and the axion-nucleon coupling $g^2/(4\pi)$ (as a function of axion mass $m_a$). The results show that, in the $1$–$2$ nm Yukawa-range window, the Casimir-Polder data strengthen previously known Casimir-force bounds by up to a factor of $33.4$, while for axionlike particles with masses $32.2$–$100$ eV they improve by up to $24.2$ relative to earlier Casimir-force constraints, though in some mass ranges one-axion H$_2$-beam bounds remain stronger. The findings demonstrate the Casimir effect’s ongoing potential to tighten constraints on new physics, particularly with reduced systematic errors enabling even sharper limits.

Abstract

We derive constraints on the parameters of the Yukawa-type interaction and on the coupling constant of axionlike particles to nucleons from the results of recent diffraction experiment on measuring the Casimir-Polder interaction between Ar atoms and a silicon nitride nanograting. It is shown that within the interaction range from 1 to 2 nm the obtained constraints are by up to a factor of 33.4 stronger than all the other ones found previously from measurement of the Casimir force. The derived constraints are weaker in strength than those deduced from the experiments on neutron scattering. The constraints on the coupling constants of axionlike particles to nucleons following from the diffraction experiment are up to a factor of 24.2 stronger withing the range of axion masses from 32.4 to 100 eV than the previously derived ones from experiments on measuring the Casimir force. They are weaker only in comparison to the constraints found from the experiment using the beams of molecular hydrogen. The potential of the Casimir effect for obtaining stronger constraints on the parameters of hypothetical interactions is discussed.

Figures (2)

• Figure 1: Constraints on the interaction constant of the Yukawa-type potential obtained from measurements of the Casimir-Polder interaction in the diffraction experiment are shown by the line labeled C-P versus the interaction range. The previously obtained constraints from measuring the Casimir force between a SiC plate and a borosilicate microsphere, the lateral and normal Casimir forces between corrugated surfaces, the effective Casimir pressure, and from the experiments on neutron scattering are shown by the lines 1, 2, 3, 4, and $n_1$, $n_2$, $n_3$, respectively. The measurement data of each mentioned experiment exclude the region of the $(\lambda,\,\alpha)$ plane above the corresponding line and allow the region below it.
• Figure 2: Constraints on the coupling constant of axionlike particles to nucleons obtained from measurements of the Casimir-Polder interaction in the diffraction experiment are shown by the line labeled C-P versus the axion mass. The previously obtained constraints from the differential force measurements, measuring the effective Casimir pressure, the lateral Casimir force between corrugated surfaces, the Casimir force between a SiC plate and a borosilicate microsphere, and the spin-dependent forces between protons in the beam of molecular hydrogen are shown by the lines 1, 2, 3, 4, and H$_2$, respectively. The measurement data of each mentioned experiment exclude the region of the $(m_a,\,g^2/(4\pi))$ plane above the corresponding line and allow the region below it.