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Paper

#### Ground-State Quantum-Electrodynamical Density-Functional Theory

##### External Resource

https://arxiv.org/abs/1509.01417

(Preprint)

##### Fulltext (public)

1509.01417.pdf

(Preprint), 155KB

##### Supplementary Material (public)

There is no public supplementary material available

##### Citation

Ruggenthaler, M. (2017). Ground-State Quantum-Electrodynamical Density-Functional Theory.

Cite as: http://hdl.handle.net/11858/00-001M-0000-0029-2339-7

##### Abstract

In this work we establish a density-functional reformulation of coupled matter-photon problems subject to general external electromagnetic fields and charge currents. We first show that for static minimally-coupled matter-photon systems an external electromagnetic field is equivalent to an external charge current. We employ this to show that scalar external potentials and transversal external charge currents are in a one-to-one correspondence to the expectation values of the charge density and the vector-potential of the correlated matter-photon ground state. This allows to establish a Maxwell-Kohn-Sham approach, where in conjunction with the usual single-particle Kohn-Sham equations a classical Maxwell equation has to be solved. In the magnetic mean-field limit this reduces to a current-density-functional theory that does not suffer from non-uniqueness problems and if furthermore the magnetic field is zero recovers standard density-functional theory.