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arXiv · 2301.00670

Simultaneous fermion and exciton condensations from a model Hamiltonian

LeeAnn M. Sager·David A. Mazziotti
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Abstract

Fermion-exciton condensation in which both fermion-pair (i.e., superconductivity) and exciton condensations occur simultaneously in a single coherent quantum state has recently been conjectured to exist. Here, we capture the fermion-exciton condensation through a model Hamiltonian that can recreate the physics of this new class of highly correlated condensation phenomena. We demonstrate that the Hamiltonian generates the large-eigenvalue signatures of fermion-pair and exciton condensations for a series of states with increasing particle numbers. The results confirm that the dual-condensate wave function arises from the entanglement of fermion-pair and exciton wave functions, which we previously predicted in the thermodynamic limit. This model Hamiltonian -- generalizing well-known model Hamiltonians for either superconductivity or exciton condensation -- can explore a wide variety of condensation behavior. It provides significant insights into the required forces for generating a fermion-exciton condensate, which will likely be invaluable for realizing such condensations in realistic materials with applications from superconductors to excitonic materials.

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LeeAnn M. Sager, David A. Mazziotti. 2022-12-29. Simultaneous fermion and exciton condensations from a model Hamiltonian. https://doi.org/10.1103/physrevb.105.035143

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