Reduced density matrix and internal dynamics for multicomponent regions

Reduced density matrix and internal dynamics for multicomponent regions

We find the density matrix corresponding to the vacuum state of a massless Dirac field in two dimensions reduced to a region of the space formed by several disjoint intervals. We calculate explicitly its spectral decomposition. The imaginary power of the density matrix is a unitary operator implementing an internal time flow (the modular flow). We show that in the case of more than one interval...

Reduced density matrix and combined dynamics of electrons and nuclei

Density Matrix Methods for Semiconductor Coulomb Dynamics

Current experiments on semiconductor devices using femtosecond lasers provide new theoretical challenges for the description of charge carrier dynamics. Among the new features of such experiments are states driven very far from equilibrium and probes on time scales short compared to scattering and other characteristic material relaxation times. Standard many-body methods must be modified and ex...

Part I Reduced Density Matrix Functional Theory

Reduced Density Matrix Functional for Many-Electron Systems

Reduced density matrix functional theory for the case of solids is presented and a new exchange correlation functional based on a fractional power of the density matrix is introduced. We show that compared to other functionals, this produces more accurate results for finite systems. Moreover, it captures the correct band gap behavior for conventional semiconductors as well as strongly correlate...