A major revision, v4.0.0 introduces a lot of new stuff including:

• Complete recoding of the core with better coding and commenting which hopefully makes it easier to implement custom features
• Modification of interfacing with parameters and results through method attributes instead of bulky dictionaries
• Stability of the half step Fourier method, allowing to use a soliton solution as an original state for the LLE
• Allowing arbitrary number of driving pump, according to Taheri et al The European Physical Journal D 2017. and our paper on Nature Communication (Moille et al. Nature Communication 2021)
• Julia compatibility with version 1.8 (current as of 05/01/2023) and above. Previous version are no longer supported

Please, if you use this package and it helps you with your research and publication, cite us in your paper. Not only does it allow us to have a better idea of new things people are interested in and how to keep improving the solver, but it also helps us build a community where everybody can help maintain the solver to better suit the needs of everybody. You can cite our paper published in the Journal of Research of the National Institute of Standards and Technology, available here, with the following BibTeX entry.:

@article{moille_pyLLE,
      author = {Gregory Moille and Qing Li and Xiyuan Lu and Kartik Srinivasan},
      title = {pyLLE: a Fast and User Friendly Lugiato-Lefever Equation Solver},
      year = {2019},
      volume = {124},
      pages = {124012},
      month = {2019-05-24},
      journal = {Journal of Research of the NIST},
       doi = {https://doi.org/10.6028/jres.124.012},
     }

As pyLLE relies on a Julia back-end, please prior to installing this package be sure that Julia is installed on your machine or visit the julia package download page to install it. The code should now work with any recent version of Julia.

Once Julia installed, the different packages needed to run pyLLE, either python or julia related, will be automatically downloaded and installed. Just a heads up, the installation of the package can vary in time, especially because of Julia that might rebuild the cache.

pyLLE will look by default to find the Julia binary in the /opt/bin/julia, which you can make it happen either in MacOS

ln -s /Applications/Julia-<version>.app/Contents/Resources/julia/bin/julia /opt/bin/julia

or Linux

ln -s <julia_path>/bin/julia /opt/bin/julia

Note that if this step is skipped it is alright as an update of the pyLLE package provide a way to specify the julia binary you would like to use specifyin solver.SolveTemporal(bin = <where julia bin is>)

Now, one can simply automatic install, just pip it :

pip install pyLLE

or pip the github

pip install git+https://github.com/gregmoille/pyLLE.git

For windows the julia package have to be installed manually, using a julia console and typing the following command:

using Pkg

Pkg.add("HDF5")
Pkg.update("HDF5")

Pkg.add("FFTW")
Pkg.update("FFTW")

Pkg.add("LinearAlgebra")
Pkg.update("LinearAlgebra")

For a manual install, download the .zip of the repository or clone it and install with the setup.py script.

Launch a julia console and within type the commands:

using HDF5
using FFTW
using LinearAlgebra

if any of the previous command throw an issue, mostly it is because it is not installed. One way to fix it is to remove the installed packaged to remove the cache

• for linux and mac os user: remove everything in ~/.julia/
• for windows users: remove everything in C:\Users<your user name>.julia\

Then enter the pacakge manager for julia by typing in the julia console:

julia>]

then

(v1.1) pkg>add HDF5
(v1.1) pkg>add FFTW

A complete example is available in the example directory notebook with the corresponding file needed in the folder. You can also access the nbviewer example to have a better idea of what's going on:

If you want to be featured here, shoot me an email! I try to keep it up to date but this is not a priority. I would love to hear anybody who uses it!

• 2023:
  • Moille, G., Stone, J., Chojnacky, et al. Kerr-Induced Synchronization of a Cavity Soliton to an Optical Reference. Nature 624, 267–274 (2023).
  • Moille, G., Lu, X., Stone, J., Westly, D., & Srinivasan, K. (2023). Fourier synthesis dispersion engineering of photonic crystal microrings for broadband frequency combs. Communications Physics, 6(1), 144.
  • Ren, D., Dong, C., & Burghoff, D. Integrated nonlinear photonics in the longwave-infrared: A roadmap. MRS Communications, 13(6), 942-956 (2023).
  • Ji, H., Geng, Z., Cheng, W., Wu, P., Yu, Z., Liu, Y., ... & Zhao, Q. (2023). High-power two-color Kerr frequency comb generation on the gallium phosphide-on-insulator platform at SWIR and MIR spectra. JOSA B, 40(8), 1976-1985.
  • Geng, Z., Ji, H., Yu, Z., Cheng, W., Wu, P., Li, Y., & Zhao, Q. (2023). Dispersion-flattened concentric structure for microcomb bandwidth broadening in GaP-OI resonators. JOSA B, 40(3), 673-681.
  • Moille, G., Li, C., Stone, J., Chojnacky, M., Shandilya, P., Chembo, Y. K., Dutt, A., ... & Srinivasan, K. (2023). Two-Dimensional Nonlinear Mixing Between a Dissipative Kerr Soliton and Continuous Waves for a Higher-Dimension Frequency Comb. arXiv preprint arXiv:2303.10026.
• 2022:
  • Afridi, A. A., Weng, H., Li, J., Liu, J., McDermott, M., Lu, Q., ... & Donegan, J. F. (2022). Breather solitons in AlN microresonators. Optics Continuum, 1(1), 42-50.
  • Lu, S., Liu, X., Shi, Y., Yang, H., Long, Z., Li, Y., ... & Liang, H. (2022). Mid-infrared ultra-broadband optical Kerr frequency comb based on a CdTe ring microresonator: a theoretical investigation. Optics express, 30(19), 33969-33979.
• 2021:
  • Weng, H., Liu, J., Afridi, A. A., Li, J., Dai, J., Ma, X. et al. "Octave-spanning Kerr frequency comb generation with stimulated Raman scattering in an AlN microresonator". Optics Letters, 46(3), 540-543. (2021)
  • Weng, H., Liu, J., Afridi, A. A., Li, J., Dai, J., Ma, X. et al. "Directly accessing octave-spanning dissipative Kerr soliton frequency combs in an AlN microring resonator" Photonics Research (2021)
  • Moille, G., Westly, D., Orji, N. G., & Srinivasan, K. "Tailoring broadband Kerr soliton microcombs via post-fabrication tuning of the geometric dispersion". Applied Physics Letters, 119(12), 121103 (2021)
  • Weng, H., Liu, J., Afridi, A. A., Li, J., Dai, J., Zhang, Y., et al. "Perfect soliton crystal in an AlN microresonator". In CLEO: QELS_Fundamental Science (pp. JTh3A-31). Optical Society of America. (2021)
  • Moille, G., Westly, D., Simelgor, G., & Srinivasan, K. "Impact of the precursor gas ratio on dispersion engineering of broadband silicon nitride microresonator frequency combs". Optics Letters, 46(23), 5970-5973 (2021).
• 2020:
  • Schuttrups, B. (2020). "Modelling nonlinear optical pulse propagation using pseudo-spectral methods" (Master's thesis, University of Twente).
  • Moille, G., Chang, L., Xie, W., Rao, A., Lu, X., Davanco, M. et al. "Dissipative Kerr Solitons in a III‐V Microresonator". Laser & Photonics Reviews, 14(8), 2000022 (2020) -2019:
  • Gregory Moille, Xiyuan Lu, Ashutosh Rao, Qing Li, Daron A. Westly, Leonardo Ranzani, Scott B. Papp, Mohammad Soltani, and Kartik Srinivasan "Kerr-Microresonator Soliton Frequency Combs at Cryogenic Temperatures," Phys. Rev. Applied 12, 034057 (2019)
  • Gregory Moille, Qing Li, Travis C. Briles, Su-Peng Yu, Tara Drake, Xiyuan Lu, Ashutosh Rao, Daron Westly, Scott B. Papp, and Kartik Srinivasan "Broadband resonator-waveguide coupling for efficient extraction of octave-spanning microcombs," Optics Letters Vol. 44, Issue 19, pp. 4737-4740 (2019)
  • Lin Chang, Weiqiang Xie, Haowen Shu, Qifan Yang, Boqiang Shen, Andreas Boes, Jon D. Peters, Warren Jin, Songtao Liu, Gregory Moille, Su-Peng Yu, Xingjun Wang, Kartik Srinivasan, Scott B. Papp, Kerry Vahala, John E. Bowers "Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators," arXiv:1909.09778 (2019)