# Enhanced Strong Interaction between Nanocavities and p-shell Excitons Beyond the Dipole Approximation

## TL;DR

This paper demonstrates enhanced strong coupling between nanocavities and p-shell excitons beyond the dipole approximation, achieved through in situ wave-function control, with potential applications in quantum photonic networks.

## Contribution

It introduces a method to enhance exciton-cavity interactions using p-shell excitons and wave-function control, surpassing the dipole approximation limitations.

## Key findings

- Achieved a coupling strength of 210 μeV.
- Demonstrated nonlocal interactions beyond the dipole approximation.
- Proposed a distributed delay model to explain coupling strength variation.

## Abstract

Large coupling strengths in exciton-photon interactions are important for quantum photonic network, while strong cavity-quantum-dot interactions have been focused on s-shell excitons with small coupling strengths. Here we demonstrate strong interactions between cavities and p-shell excitons with a great enhancement by the \textit{in situ} wave-function control. The p-shell excitons are demonstrated with much larger wave-function extents and nonlocal interactions beyond the dipole approximation. Then the interaction is tuned from the nonlocal to local regime by the wave-function shrinking, during which the enhancement is obtained. A large coupling strength of $210\ \mu\mathrm{eV}$ has been achieved, indicating the great potential of p-shell excitons for coherent information exchange. Furthermore, we propose a distributed delay model to quantitatively explain the coupling strength variation, revealing the intertwining of excitons and photons beyond the dipole approximation.