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Many-Body Perturbation Theory for Driven Dissipative Quasiparticle Flows and Fluctuations
Thomas Blommel1,2, Enrico Perfetto3,4, Gianluca Stefanucci3,4
1University of California, Santa Barbara, Department of Chemistry and Biochemistry, California, USA.
Physical Review Letters
|July 10, 2026
Summary
We developed a new theory for open quantum systems, unifying dissipation, correlations, and driving. This approach enables accurate simulations of quantum materials, revealing enhanced quasiparticle stability and lifetimes.
Area of Science:
- Quantum physics
- Condensed matter theory
- Many-body perturbation theory
Background:
- Open quantum systems are challenging due to dissipation, correlations, and external driving.
- Existing theories struggle to treat these factors simultaneously and on equal footing.
- Accurate modeling of quantum materials requires a unified theoretical framework.
Purpose of the Study:
- To present a unified many-body perturbation theory for open quantum systems.
- To incorporate dissipation, correlations, and external driving within a single formalism.
- To enable first-principles modeling of complex quantum materials.
Main Methods:
- Utilizing a Keldysh-Lindblad formalism.
- Introducing a diagrammatic treatment with new Feynman rules for dissipative interactions.
- Preserving Keldysh and anti-Hermitian symmetries for Kadanoff-Baym equations.
- Deriving dissipative second Born and GW approximations.
Main Results:
- Developed a compact and systematically improvable diagrammatic approach.
- Maintained the structure of Kadanoff-Baym equations for direct application of numerical methods.
- Demonstrated efficient simulation of relaxation and decoherence dynamics.
- Observed dissipation-induced correlations leading to quasiparticle stabilization and extended lifetimes in the driven Haldane model.
Conclusions:
- The presented framework offers a general route for first-principles modeling of correlated, driven, and dissipative quantum materials.
- The theory successfully unifies key aspects of open quantum systems, paving the way for new discoveries.
- The method allows for accurate prediction of quantum material properties under realistic conditions.
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