Ph. Lecheminant | Searcharxiv

arXiv2016

Particle Formation and Ordering in Strongly Correlated Fermionic Systems: Solving a Model of Quantum Chromodynamics

In this paper we study a (1+1)-dimensional version of the famous Nambu-Jona-Lasinio model of Quantum Chromodynamics (QCD2) both at zero and finite hadron density. We use non-perturbative techniques (non-Abelian bosonization and Truncated Conformal Space Approach). At zero density we describe a formation of fermion three-quark (nucleons and $Δ$-baryons) and boson (two-quark mesons, six-quark deuterons) bound states and also a formation of a topologically nontrivial phase. At finite hadron density, the model has a rich phase diagram which includes phases with density wave and superfluid quasi-long-range (QLR) order and also a phase of a baryon Tomonaga-Luttinger liquid (strange metal). The QLR order results as a condensation of scalar mesons (the density wave) or six-quark bound states (deuterons).

hep-th↗

arXiv2002

Chiral order in spin-S XY chains

We consider the issue of chiral ordering in spin chains for an arbitrary value of the spins S. By use of bosonization according to a scheme developped by H.-J. Schulz, we obtain the phase diagram of the chain with XY exchange between nearest and next-to-nearest neighbors. We obtain a satisfactory picture including a chiral spin nematic phase which is gapless, has long-range chiral order and incommensurate spin correlations. We perform a stability analysis of this phase and point out that this analysis is in conflict with existing DMRG results that shows a difference between integer and half-integer spin case.

cond-mat.str-el↗