Condensation of Composite Bosonic Trions in Interacting Bose-Fermi Mixtures

TL;DR

This paper uncovers a quantum coherent state in one-dimensional Bose-Fermi mixtures where composite bosonic trions form, revealing a new three-body pairing mechanism with potential implications for quantum many-body physics.

Contribution

It demonstrates the emergence of composite bosonic trions in Bose-Fermi mixtures through two models, supported by DMRG calculations showing quasi-condensation and unique correlation behaviors.

Findings

Observation of algebraically decaying trion correlations

Detection of gapped single-particle excitations

Suppressed fermion pair correlations

Abstract

We reveal a quantum coherent state characterized by composite bosonic trions, wherein paired fermions further bind with bosons, in one-dimensional Bose-Fermi mixtures.This phase emerges in two separate models, both featuring onsite boson-fermion attraction that induces negative binding energy for the composite trions. The first is the pair-hopping model, in which spinless fermions undergo pair hopping to form preformed pairs. The second is the extended Bose-Fermi Hubbard model, describing dipolar bosons and fermions with density-density interactions. Notably, the formation of composite trions is independent of the specific pairing interactions of fermions. Extensive density matrix renormalization group calculations demonstrate the quasi-condensation of the composite trions, evidenced by algebraically decaying correlations of trions, gapped single-particle excitations, and suppressed fermion pair correlations. Our findings provide valuable insights into the three-body pairing mechanism in mixed-particle systems.