Effects of higher-order Casimir-Polder interactions on Rydberg atom spectroscopy
Bhaskar Dutta, J. C. de Aquino Carvalho, G. Garcia‐Arellano, P. Pedri, Athanasios Laliotis, Chris Boldt, Jivesh Kaushal, Stefan Scheel
Abstract
In the extreme near field, when the spatial extension of the atomic wavefunction is no longer negligible compared to the atom-surface distance, the dipole approximation is no longer sufficient to describe Casimir-Polder interactions. Here we calculate the higher-order, quadrupole and octupole, contributions to Casimir-Polder energy shifts of Rydberg atoms close to a dielectric surface. We subsequently investigate the effects of these higher-order terms in thin-cell and selective reflection spectroscopy. Beyond its fundamental interest, this regime of extremely small atom surface separations is relevant for quantum technology applications with Rydberg or surface-bound atoms interfacing with photonic platforms. Published by the American Physical Society 2024