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arXiv · 2109.10320

Operatorial formulation of the ghost rotationally-invariant slave-Boson theory

Nicola Lanatà
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Abstract

We propose an operatorially-exact formalism for describing the equilibrium and quantum-dynamical properties of many-electron systems interacting locally on a lattice, called "ghost rotationally-invariant slave-Boson theory" (g-RISB). We demonstrate that our theoretical framework reduces to the recently-developed ghost Gutzwiller approximation (g-GA) at the mean-field level. Furthermore, we introduce the time-dependent mean-field g-RISB action, generalizing the time-dependent GA theory. Since the g-RISB is based on exact reformulation of the many-body problem, it may pave the way to the development of practical implementations for adding systematically quantum-fluctuation corrections towards the exact solution, in arbitrary dimension.

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Nicola Lanatà. 2021-09-21. Operatorial formulation of the ghost rotationally-invariant slave-Boson theory. https://doi.org/10.1103/physrevb.105.045111

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