DefectPL

A comprehensive toolkit for calculating and visualizing photoluminescence spectra of quantum defects. It also supports the analysis of other optical properties of point defects in insulators and semiconductors.

⚠️ This package is currently under active development.

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📌 Purpose

DefectPL is designed to compute the photoluminescence intensity of point defects in solids using the methodology described in New J. Phys. 16 (2014) 073026. It also provides tools to calculate and plot related quantities such as:

• Partial Huang-Rhys factors
• Huang-Rhys factor
• Debye-Waller factor
• Inverse participation ratios (IPR)
• Localization ratios
• Vibrational displacements
• Effect of Isotope substitution
• Photoluminescence Spectra in the High Huang-Rhys Factor Regime

If you use this package in your research, please consider citing:

Carbon with Stone-Wales defect as quantum emitter in h-BN, Phys. Rev. B 111, 104109 (2025)

Read the article

High-throughput computational search for group-IV-related quantum defects as spin-photon interfaces in 4H-SiC, ChemRxiv (2025)

Read the article

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📚 Documentation

Full documentation is available at: https://Shibu778.github.io/defectpl/

🚀 Installation

Install via pip:

pip install defectpl

Install via conda:

conda install conda-forge::defectpl

Install from GitHub:

git clone https://github.com/Shibu778/defectpl.git
cd defectpl/defectpl
pip install -e .

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🧑‍💻 Example Usage

Here’s a minimal example using data for a negative NV center in diamond:

from defectpl.defectpl import DefectPl

band_yaml = "../tests/data/band.yaml"
contcar_gs = "../tests/data/CONTCAR_gs"
contcar_es = "../tests/data/CONTCAR_es"
out_dir = "./plots"
EZPL = 1.95
gamma = 2
plot_all = True
iplot_xlim = [1000, 2000]

defctpl = DefectPl(
    band_yaml,
    contcar_gs,
    contcar_es,
    EZPL,
    gamma,
    iplot_xlim=iplot_xlim,
    plot_all=plot_all,
    out_dir=out_dir,
)

Plots Gallery

Intensity vs Phonon Energy	Spectral Function, Partial HR factor and Localization Ratio
Vibrational Displacement	Phonon Energy
Inverse Participation Ratio	Localization Ratio
Partial HR factor (pHR)	Spectral Function, pHR
Spectral Function, Partial HR factor and IPR	One Dimensional Vibrational Spectra

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🤝 Contributing

Contributions, suggestions, and bug reports are welcome!
If you encounter any issues, please open an issue or submit a pull request.

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👤 Author

Main Maintainer: Shibu Meher, Manoj Dey