ctseg
ctseg: A focused, open-source solver for density-density quantum impurity models in TRIQS workflows. Ranked #82 of 89 in Physics Simulation Software by our editors (3.0/10); pricing: Free plan; best for researchers solving quantum impurity models.
At a glance
- Editor score3.0 / 10
- PricingFree plan
- Best forResearchers solving quantum impurity models
- Free planYes
- Paid fromFree
- Delivery modeDesktop
- Facts checked24 Sep 2026
Where it wins
- Implements the continuous-time segment quantum Monte Carlo algorithm
- Measures Green functions, correlations, and other imaginary-time observables
- Open source, local, and integrated with TRIQS
Where it doesn't
- Limited to quantum impurity models with density-density interactions
- Requires a local TRIQS-based Python/C++ workflow
- Support is through documentation and community
Our verdict on ctseg
For computational condensed-matter and many-body physics researchers, ctseg is a local software library that solves quantum impurity models with density-density interactions. It implements a continuous-time segment quantum Monte Carlo algorithm, sampling impurity configurations and measuring Green functions, correlations, and other observables in imaginary time. This is a specialized research tool rather than a hosted teaching application, so it suits researchers working within the relevant computational methods and TRIQS ecosystem, not users seeking general-purpose physics simulation software.
Its scope is deliberately focused: the segment algorithm and density-density interaction model define what it can address. The measurement capabilities provide useful outputs for impurity-model studies, including Green-function and correlation data. Researchers needing another interaction model or a broader simulation environment should assess whether a different solver fits their methods; ctseg is not positioned as an all-purpose simulator.
ctseg is open source and runs locally on Linux and macOS, with desktop and self-hosted deployment options and offline access. Its integration with TRIQS supports use in TRIQS-based Python/C++ workflows. Documentation and community are the stated support channels, which makes familiarity with the surrounding research software workflow important. Choose ctseg when its model and algorithm match the research problem and local TRIQS use is appropriate; look elsewhere if you need a hosted interface, broader model coverage, or another support arrangement.
Your product? Our editors can test ctseg in depth and publish a review, labelled as paid · from $149/mo →
ctseg pricing
ctseg fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Delivery mode | Desktop |
| Lesson library | Not verified |
| Authoring tools | Not verified |
| Assessment tools | Not verified |
| 3D visuals | Not verified |
| Offline access | Yes |
| Data export | Not verified |
| Deployment | Self-hosted, Desktop |
| Platforms | Linux, macOS |
| Support | Docs, Community |
| Built for | Mid-market, Enterprise (editorial estimate) |
| Integrations | 1 integrations: TRIQS |
| Pricing | Free plan |
| Website | triqs.github.io |
| Facts checked | 24 Sep 2026 |
ctseg integrations
ctseg lists 1 integrations on its own site.
- TRIQS
Alternatives to ctseg
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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