# Electric field excitation suppression in cold atoms

## TL;DR

This paper investigates how electric fields, both external and generated by ionized charges, suppress atomic excitation in cold rubidium atoms, with implications for quantum information and plasma creation.

## Contribution

It introduces a detailed study of excitation suppression mechanisms via Coulomb blockade caused by ion-generated electric fields in cold atoms.

## Key findings

- Charge-dipole interaction causes excitation suppression.
- Interaction potential scales as 1/R^2, frequency shift as 1/R^4.
- Experimental validation with $^{85}$Rb atoms.

## Abstract

In this article, the atom excitation suppression is studied in two ways. The first way of exploring the excitation suppression is by an external DC electric field. The second way is to study the excitation suppression caused by electric field generated by free charges, which are created by ionizing atoms. This suppression is called Coulomb blockade. Here the Coulomb forces are created by ions through ionizing atoms by a UV laser. The theory shows that the interaction, which causes the suppression, is primarily caused by charge-dipole interactions. Here the charge is the ion, and the dipole is an atom. In this experiment, we use $^{85}$Rb atoms. The valence electron and the ion core are the two poles of an electric dipole. The interaction potential energy between the ion and the atom is proportional to $\frac{1}{R^2}$, and the frequency shift caused by this interaction is proportional to $\frac{1}{R^4}$, where $R$ is the distance between the ion and the dipole considered. This research can be used for quantum information storage, remote control, creating hot plasmas using cold atoms, as well as electronic devices.