Nonequilibrium Green function approach to the pair distribution function of quantum many-body systems out of equilibrium

@article{Bonitz2013NonequilibriumGF,
  title={Nonequilibrium Green function approach to the pair distribution function of quantum many-body systems out of equilibrium},
  author={Michael Bonitz and Sebastian Hermanns and Karin Kobusch and Karsten Balzer},
  journal={Journal of Physics: Conference Series},
  year={2013},
  volume={427},
  pages={012002}
}
The pair distribution function (PDF) is a key quantity for the analysis of correlation effects of a quantum system both in equilibrium and far from equilibrium. We derive an expression for the PDF in terms of the single-particle Green functions—the solutions of the Keldysh/Kadanoff-Baym equations in the two-time plane—for a one- or two-component system. The result includes initial correlations and generalizes previous density matrix expressions from single-time quantum kinetic theory. Explicit… 
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References

SHOWING 1-10 OF 41 REFERENCES
Electronic double excitations in quantum wells: Solving the two-time Kadanoff-Baym equations
For a quantum many-body system, the direct population of states of double-excitation character is a clear indication that correlations importantly contribute to its nonequilibrium properties. We
The non-equilibrium Green function approach to inhomogeneous quantum many-body systems using the generalized Kadanoff–Baym ansatz
In the non-equilibrium Green function calculations, the use of the generalized Kadanoff–Baym ansatz (GKBA) allows for a simple approximate reconstruction of the two-time Green function from its
Relaxation of a quantum many‐body system from a correlated initial state. A general and consistent approach
Various approaches to a theoretical treatment of the dynamics of quantum many‐body systems starting from a correlated initial state are discussed. In particular, we compare the concept of the
Nonequilibrium Green's function approach to strongly correlated few-electron quantum dots
The effect of electron-electron scattering on the equilibrium properties of few-electron quantum dots is investigated by means of nonequilibrium Green's function theory. The ground and equilibrium
Real-time kadanoff-baym approach to plasma oscillations in a correlated electron gas.
TLDR
It is shown that solving Kadanoff-Baym-type equations of motion for the two-time correlation functions including the external perturbing field allows one to compute the plasmon spectrum with collision effects in a systematic and consistent way.
Configuration Path Integral Monte Carlo
A novel path integral Monte Carlo (PIMC) approach for correlated many‐particle systems with arbitrary pair interaction in continuous space at low temperatures is presented. It is based on a
Two-particle problem in a nonequilibrium many-particle system.
TLDR
It turns out that results obtained earlier are valid only in limiting cases of a nondegenerate system or a static interaction, respectively, and the differences to former results obtained for the effective two-particle Hamiltonian are discussed.
Non-Markovian Boltzmann Equation
Abstract A quantum kinetic equation for strongly interacting particles (generalized binary collision approximation, ladder or T-matrix approximation) is derived in the framework of the density
Numerical analysis of non-Markovian effects in charge-carrier scattering: one-time versus two-time kinetic equations
The non-Markovian carrier - carrier scattering dynamics in a dense electron gas is investigated. Within the framework of quantum kinetic equations in the second Born approximation we study the
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