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Dynamical Complexity of Non-Gaussian Many-Body Systems with Dissipation
Guillermo González-García1,2, Alexey V Gorshkov3,4, J Ignacio Cirac1,2
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Straße 1, 85748 Garching, Germany.
Physical Review Letters
|November 21, 2025
Summary
High dissipation in many-body fermionic and bosonic systems can lead to classical sampling. Dissipation can simplify fermionic states but not necessarily bosonic ones, with entanglement generation differing between the two.
Area of Science:
- Quantum many-body physics
- Quantum information theory
- Statistical mechanics
Background:
- Understanding the dynamics of open quantum systems is crucial for quantum technologies.
- Characterizing the states of bosonic and fermionic systems with dissipation presents significant theoretical challenges.
Purpose of the Study:
- To characterize the dynamical states of many-body bosonic and fermionic models under various types of dissipation.
- To identify conditions under which these systems can be efficiently sampled by classical algorithms.
- To explore the differences in state evolution and entanglement generation between bosonic and fermionic systems.
Main Methods:
- Analysis of many-body models with intersite Gaussian couplings, on-site non-Gaussian interactions, and local dissipation (particle loss, gain, dephasing).
- Derivation of conditions for system states to be convex combinations of Gaussian states (fermionic) or separable states (bosonic).
- Investigation of the existence of classical algorithms for efficient state sampling above certain noise thresholds.
Main Results:
- For fermionic systems, strong dephasing noise drives the system into a convex combination of Gaussian states.
- For bosonic systems, strong particle loss and gain lead to separable states.
- A classical sampling algorithm is efficient for both models when noise rates exceed a threshold.
- Unlike fermionic systems, bosonic systems can evolve into non-Gaussian states even with high dissipation.
- Unlike bosonic systems, fermionic systems can generate entanglement even with high noise rates.
Conclusions:
- The interplay between interactions and dissipation dictates the complexity of many-body quantum states.
- Specific dissipation regimes allow for efficient classical simulation of both fermionic and bosonic systems.
- Fundamental differences persist in entanglement generation and state complexity between bosonic and fermionic systems under dissipation.
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