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arXiv · 1811.06066

Emergent mode and bound states in single-component one-dimensional lattice fermionic systems

Yuchi He·Binbin Tian·David Pekker·Roger S. K. Mong
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Abstract

We study the formation of bound states in a one-dimensional, single-component Fermi chain with attractive interactions. The phase diagram, computed from DMRG (density matrix renormalization group), shows not only a superfluid of paired fermions (pair phase) and a liquid of fermion triplets (trion phase), but also a phase with two gapless modes. We show that the latter phase is described by a 2-component Tomonaga-Luttinger liquid (TLL) theory, consisting of one charged and one neutral mode. We argue based on our numerical data, that the single, pair, and trion phases are descendants of the 2-component TLL theory. We speculate on the nature of the phase transitions amongst these phases.

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Yuchi He, Binbin Tian, David Pekker, Roger S. K. Mong. 2018-11-14. Emergent mode and bound states in single-component one-dimensional lattice fermionic systems. https://doi.org/10.1103/physrevb.100.201101

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