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arXiv · 2107.04335

Extending Density Matrix Embedding: A Static Two-Particle Theory

Charles J. C. Scott·George H. Booth
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Abstract

We introduce Extended Density Matrix Embedding Theory (EDMET), a static quantum embedding theory explicitly self-consistent with respect to local two-body physics. This overcomes the biggest practical and conceptual limitation of more traditional one-body embedding methods, namely the lack of screening and treatment of longer-range interactions. This algebraic zero-temperature embedding augments a local interacting cluster model with a minimal number of bosons from a description of the full system correlations via the random phase approximation, and admits an analytic approach to build a self-consistent Coulomb-exchange-correlation kernel. For extended Hubbard models with non-local interactions, this leads to the accurate description of phase transitions, static quantities and dynamics. We also move towards ab initio systems via the Parriser--Parr--Pople model of conjugated coronene derivatives, finding good agreement with experimental optical gaps.

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Charles J. C. Scott, George H. Booth. 2021-11-25. Extending Density Matrix Embedding: A Static Two-Particle Theory. https://doi.org/10.1103/physrevb.104.245114

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