Intermediate-range Casimir-Polder interaction probed by high-order slow atom diffraction

TL;DR

This study uses slow atom diffraction through a nanograting to sensitively measure the Casimir-Polder potential at nanometer distances, revealing a significant difference between nonretarded and retarded regimes.

Contribution

It introduces a novel experimental approach employing slow atom diffraction for high-precision measurement of the Casimir-Polder interaction at nanometer scales.

Findings

Detected a 15% difference between nonretarded and retarded potentials at <51 nm

Demonstrated high sensitivity of slow atom diffraction to Casimir-Polder forces

Provided detailed analysis of parameters influencing the potential

Abstract

At nanometer separation, the dominant interaction between an atom and a material surface is the fluctuation-induced Casimir-Polder potential. We demonstrate that slow atoms crossing a silicon nitride transmission nanograting are a remarkably sensitive probe for that potential. A 15% difference between nonretarded (van der Waals) and retarded Casimir-Polder potentials is discernible at distances smaller than 51 nm. We discuss the relative influence of various theoretical and experimental parameters on the potential in detail. Our work paves the way to high-precision measurement of the Casimir-Polder potential as a prerequisite for understanding fundamental physics and its relevance to applications in quantum-enhanced sensing.