rydstate 0.11.0

A Python package for calculating Rydberg wavefunctions.

RydState - A Rydberg State Calculator

The RydState software calculates properties of Rydberg states. We especially focus on the calculation of the radial wavefunction of Rydberg states via the Numerov method. The software can be installed via pip (requires Python >= 3.10):

pip install rydstate

To install the latest development version from github, use:

pip install git+https://github.com/pairinteraction/rydstate

How to Cite

This package relies on quantum defects provided by the community. Consider citing relevant publications for your atomic species.

Click to expand for quantum defect references

Element	Model	Identifier	References
H	SQDT	H	Schrödinger equation for hydrogen
Li	SQDT	Li	10.1017/CBO9780511524530 (1994) 10.1103/PhysRevA.34.2889 (1986)
Na	SQDT	Na	10.1088/0953-4075/30/10/009 (1997) 10.1070/QE1995v025n09ABEH000501 (1995) 10.1103/PhysRevA.45.4720 (1992)
K	SQDT	K	10.1088/0031-8949/27/4/012 (1983) 10.1016/0030-4018(81)90225-X (1981)
Rb	SQDT	Rb	10.1103/PhysRevA.83.052515 (2011) 10.1103/PhysRevA.74.054502 (2006) 10.1103/PhysRevA.74.062712 (2006) 10.1103/PhysRevA.67.052502 (2003)
Cs	SQDT	Cs	10.1103/PhysRevA.93.013424 (2016) 10.1103/PhysRevA.35.4650 (1987) 10.1103/PhysRevA.26.2733 (1982)
Sr88	SQDT	Sr88_sqdt	10.1103/PhysRevA.108.022815 (2023) 10.17169/refubium-34581 (2022) 10.1016/j.cpc.2020.107814 (2021)
Sr87	MQDT	Sr87_mqdt	10.1088/1361-6455/ab4c22 (2019)
Sr88	MQDT	Sr88_mqdt	10.1088/1361-6455/ab4c22 (2019)
Yb171	MQDT	Yb171_mqdt	10.1103/PhysRevX.15.011009 (2025) 10.1103/mzsv-rckx (2025)
Yb173	MQDT	Yb173_mqdt	MQDT model formulated by Frederic Hummel
Yb174	MQDT	Yb174_mqdt	10.1103/PhysRevX.15.011009 (2025) 10.1103/mzsv-rckx (2025)

Documentation

User Guide

• Tutorials - Examples of how to use the RydState library.

• API Reference - Documentation of classes and functions of the RydState Python library.

Using custom quantum defects

To use custom quantum defects (or quantum defects for a new species), you can simply create a subclass of rydstate.species.SpeciesObjectSQDT (e.g. class CustomRubidium(SpeciesObjectSQDT):) with a custom species name (e.g. name = "Custom_Rb"). Then, similarly to rydstate.species.sqdt.rubidium.py you can define the quantum defects (and model potential parameters, ...) for your species. Finally, you can use the custom species by simply calling rydstate.RydbergStateSQDTAlkali("Custom_Rb", n=50, l=0, j=1/2, m=1/2) (the code will look for all subclasses of SpeciesObjectSQDT until it finds one with the species name "Custom_Rb").

Contributors

This software is currently maintained by:

• Johannes Mögerle

The following people have made significant contributions:

• Frederic Hummel - Supported the development of the MQDT implementation. Author of the MQDT.jl Julia package, on which this package’s Python implementation of the MQDT calculations is based.
• Sebastian Weber - Provided substantial input on the physics and software architecture of this package.

We warmly welcome new contributions!

License

The rydstate software is licensed under LGPL v3. For more information, see LICENSE.txt.