Yambo

Official Resources

• Homepage: http://www.yambo-code.eu/
• Documentation: http://www.yambo-code.eu/wiki/
• Source Repository: https://github.com/yambo-code/yambo
• License: GNU General Public License v2.0

Overview

Yambo is an open-source code for calculating excited state properties of materials from first principles using many-body perturbation theory. It implements the GW approximation for quasiparticle corrections and the Bethe-Salpeter equation for optical properties, featuring user-friendly interfaces and comprehensive capabilities for studying electronic excitations in molecules and solids.

Scientific domain: Many-body perturbation theory, GW, BSE, optical properties, excited states
Target user community: Researchers studying electronic excitations, quasiparticle properties, and optical spectra

Theoretical Methods

• GW approximation (G₀W₀, evGW, qsGW)
• Bethe-Salpeter equation (BSE)
• Time-Dependent Hartree-Fock (TDHF)
• Time-Dependent DFT (TDDFT)
• Dynamical Berry phase
• Real-time propagation
• Non-equilibrium Green's function (NEGF)
• Full-frequency integration (Real-axis, Godby-Needs, Plasmon-Pole)
• Hartree-Fock exchange
• Hybrid functionals
• Spin-orbit coupling

Capabilities (CRITICAL)

• GW quasiparticle energies and band structures
• Optical absorption spectra including excitonic effects (BSE)
• Electron energy loss spectroscopy (EELS)
• Optical conductivity and dielectric function (RPA/BSE)
• Real-time propagation (improved in v5.3)
• Non-linear optics (SHG, DFG, multipole approximation - v5.2+)
• GPU acceleration (CUDA/OpenACC via devxlib - v5.3)
• Spin-orbit coupling and magnetic systems
• Interfaces with Quantum ESPRESSO, ABINIT
• Massively parallel (MPI/OpenMP/GPU)

Sources: Official Yambo documentation (v5.3), cited in 7/7 source lists

Inputs & Outputs

• Input formats:

  • DFT outputs from interfaced codes
  • Yambo input files (parameter-based)
  • Database files from DFT calculations

• Output data types:

  • Quasiparticle energies
  • Optical spectra
  • Dielectric functions
  • Self-energies
  • Screening functions
  • BSE eigenvalues and eigenvectors

Interfaces & Ecosystem

• DFT interfaces:

  • Quantum ESPRESSO (primary)
  • ABINIT
  • PWscf
  • ETSF format support

• Post-processing:

  • yambopy - Python interface
  • Analysis scripts and utilities
  • Plotting tools

• Workflow integration:

  • AiiDA-Yambo plugin
  • Can be scripted for automated calculations

Limitations & Known Constraints

• Computational cost: GW and BSE very expensive; limited to ~100-200 atoms
• Memory intensive: Self-energy and screening matrices large
• DFT dependency: Requires converged DFT ground state from external code
• k-point convergence: Often requires dense k-meshes
• Frequency grid: Convergence testing needed
• Parallelization: Complex; requires understanding of distribution
• Learning curve: Many-body methods require theoretical background
• Documentation: Good but assumes GW/BSE knowledge
• Input complexity: Many parameters to converge
• Platform: Primarily Linux/Unix; HPC recommended

Verification & Sources

Primary sources:

1. Official website: http://www.yambo-code.org/
2. Documentation: http://www.yambo-code.org/wiki/
3. GitHub repository: https://github.com/yambo-code/yambo
4. A. Marini et al., Comput. Phys. Commun. 180, 1392 (2009) - Yambo code
5. D. Sangalli et al., J. Phys.: Condens. Matter 31, 325902 (2019) - Yambo developments

Secondary sources:

1. Yambo tutorials and schools
2. yambopy documentation
3. Published GW/BSE applications
4. Confirmed in 7/7 source lists (claude, g, gr, k, m, q, z)

Confidence: CONFIRMED - Appears in all 7 independent source lists

Verification status: ✅ VERIFIED

• Official homepage: ACCESSIBLE
• Documentation: COMPREHENSIVE and ACCESSIBLE
• Source code: OPEN (GitHub)
• Community support: Very active (forum, schools, workshops)
• Academic citations: >800 (main papers)
• Active development: Regular releases, new features