From Ferrimagnetic Insulator to superconducting Luther-Emery Liquid: A DMRG Study of the Two-Leg Lieb Lattice
Fuente:
arXiv
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866917387519918080 |
|---|---|
| author | Nikolaenko, Alexander Sachdev, Subir |
| author_facet | Nikolaenko, Alexander Sachdev, Subir |
| contents | Motivated by recent experiments on ultracold fermionic spin-1/2 $^6$Li atoms in a Lieb lattice at various Hubbard repulsion $U$ and filling fractions $n$ (Lebrat et al., arXiv:2404.17555), we conduct a density matrix renormalization group (DMRG) analysis of the Hubbard model on a two-leg Lieb ladder. At half-filling, we find a ferrimagnetic Mott insulating ground state, consistent with Lieb's theorem. Away from half-filling, a state with finite total spin $\vec{S}^2 \neq 0$ and vanishing charge gap persists down to filling $n_c \approx 2/3$. For lower, incommensurate fillings, the system is described by a Luttinger liquid with one charge and one spin mode. Intriguingly, in a narrow window near $n_c = 2/3$, close to the onset of ferromagnetic order, we identify a superconducting Luther-Emery phase with dominant $s_{xy}$-wave pairing. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2604_05027 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | From Ferrimagnetic Insulator to superconducting Luther-Emery Liquid: A DMRG Study of the Two-Leg Lieb Lattice Nikolaenko, Alexander Sachdev, Subir Strongly Correlated Electrons Superconductivity Motivated by recent experiments on ultracold fermionic spin-1/2 $^6$Li atoms in a Lieb lattice at various Hubbard repulsion $U$ and filling fractions $n$ (Lebrat et al., arXiv:2404.17555), we conduct a density matrix renormalization group (DMRG) analysis of the Hubbard model on a two-leg Lieb ladder. At half-filling, we find a ferrimagnetic Mott insulating ground state, consistent with Lieb's theorem. Away from half-filling, a state with finite total spin $\vec{S}^2 \neq 0$ and vanishing charge gap persists down to filling $n_c \approx 2/3$. For lower, incommensurate fillings, the system is described by a Luttinger liquid with one charge and one spin mode. Intriguingly, in a narrow window near $n_c = 2/3$, close to the onset of ferromagnetic order, we identify a superconducting Luther-Emery phase with dominant $s_{xy}$-wave pairing. |
| title | From Ferrimagnetic Insulator to superconducting Luther-Emery Liquid: A DMRG Study of the Two-Leg Lieb Lattice |
| topic | Strongly Correlated Electrons Superconductivity |
| url | https://arxiv.org/abs/2604.05027 |