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arXiv · 2008.06633

How to define quantum mean-field solvable Hamiltonians using Lie algebras

Artur F. Izmaylov·Tzu-Ching Yen
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Abstract

Necessary and sufficient conditions for quantum Hamiltonians to be exactly solvable within mean-field theories have not been formulated so far. To resolve this problem, first, we define what mean-field theory is, independently of a Hamiltonian realization in a particular set of operators. Second, using a Lie-algebraic framework we formulate a criterion for a Hamiltonian to be mean-field solvable. The criterion is applicable for both distinguishable and indistinguishable particle cases. For the electronic Hamiltonians, our approach reveals the existence of mean-field solvable Hamiltonians of higher fermionic operator powers than quadratic. Some of the mean-field solvable Hamiltonians require different sets of quasi-particle rotations for different eigenstates, which reflects a more complicated structure of such Hamiltonians.

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Artur F. Izmaylov, Tzu-Ching Yen. 2021-06-11. How to define quantum mean-field solvable Hamiltonians using Lie algebras. https://doi.org/10.1088/2058-9565%2Fac1040

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