# An Introduction to ARC 3.0: Alkali.ne Rydberg Calculator¶

Authors: Elizabeth J. Robertson, Nikola Šibalić, Robert M. Potvliege, Matthew P. A. Jones

Updated 15/11/2020

This notebooks gives examples of new functionality introduced in ARC version 3.0: support for calculations of states, Stark maps and pair-state interactions for Alkaline Earths, pertubative van der Waals $C_6$ calculations in manifold of energy-degenerate states, inter-species pair-state calculatons, and general new calculation methods for working with Wavefunctions (supported for Alkali only), Optical lattices in 1D (calculation of recoil energies, Bloch bands, Wannier states...), atom-surface van der Waals interactions and calculation of dynamic polarisabilities (magic wavelengths and other details useful for atom-trapping). For introduction to Rydberg-state calculations, also available in the original ARC version, we point users to the An Introduction to Rydberg atoms with ARC . For general introduction into physics of Rydberg states and their properties and applications see Rydberg Physics ebook published by IOP.

For preprint detailing this extension plese see arxiv:2007.12016

Contents:

# Preliminaries: general note on using ARC with Alkaline Earths¶

Dipole matrix elements for Alkaline Earths are calculated using single active electron approximation. DME are calculated based using semi-classical approximation. DME obtained in this way are in general correct for higher lying states only. See publication for details.

To use ARC in your Python project, import module as

# General atom calculations with Alkaline earths¶

NOTE: Interactive clickable plot, allowing finding wavelengths and frequencies for transitions beteen different states, opens if used from command line as in in python code.py or if notebook is initialised with stand-alone, instead inline figures. This requires calling following line after import of arc:

We will use inline plots for the rest of this notebook, but it's easy to switch