Zobrazeno 1 - 10
of 309
pro vyhledávání: '"Iskin, M."'
Autor:
Iskin, M.
We study the size of two-body bound states and Cooper pairs within a multiband Hubbard model that features time-reversal symmetry and uniform pairing on a generic lattice. Our analysis involves (i) an exact calculation of the localization tensor to d
Externí odkaz:
http://arxiv.org/abs/2409.14921
Autor:
Iskin, M.
Publikováno v:
Phys. Rev. B 110, 144505 (2024)
To explore the influence of quantum-geometric effects on the Ginzburg-Landau coherence length in a dilute flat-band superconductor, we adopt a BCS-BEC crossover approach to the multiband pyrochlore-Hubbard model near the critical temperature for supe
Externí odkaz:
http://arxiv.org/abs/2407.08449
Autor:
Iskin, M.
Publikováno v:
Physics Letters A 523, 129781 (2024)
Considering a spin-up and a spin-down fermion in a generic tight-binding lattice with a multi-site basis, we investigate the two-body problem using a multiband extended-Hubbard model with finite-ranged hopping and interaction parameters. We derive a
Externí odkaz:
http://arxiv.org/abs/2404.01117
Autor:
Iskin, M.
Publikováno v:
Phys. Rev. B 109, 174508 (2024)
We investigate the impacts of the quantum geometry of Bloch states, specifically through the band-resolved quantum-metric tensor, on Cooper pairing and flat-band superconductivity in a three-dimensional pyrochlore-Hubbard model. First we analyze the
Externí odkaz:
http://arxiv.org/abs/2403.04270
Autor:
Alyuruk, D. C., Iskin, M.
Publikováno v:
Phys. Rev. B 109, 035149 (2024)
We analyze the two-body spectrum within the Hofstadter-Hubbard model on a square lattice through an exact variational ansatz and study the topological properties of its low-lying two-body bound-state branches. In particular we discuss how the Hofstad
Externí odkaz:
http://arxiv.org/abs/2310.09565
Autor:
Iskin, M.
Publikováno v:
Phys. Rev. A 107, 053323 (2023)
In a multiband Hubbard model the self-consistency relations for the two-body bound-state bands are in the form of a nonlinear eigenvalue problem. Assuming that the resultant eigenvectors form an orthonormal set, e.g., in the strong-binding regime, he
Externí odkaz:
http://arxiv.org/abs/2305.08494
Autor:
Iskin, M.
Publikováno v:
Phys. Rev. B 107, 224505 (2023)
We first apply functional-integral approach to a multiband Hubbard model near the critical pairing temperature, and derive a generic effective action that is quartic in the fluctuations of the pairing order parameter. Then we consider time-reversal-s
Externí odkaz:
http://arxiv.org/abs/2304.03613
Autor:
Iskin, M.
Publikováno v:
Phys. Rev. A 107, 023313 (2023)
We consider a weakly-interacting Bose-Einstein condensate (BEC) that is loaded into an optical lattice with a two-point basis, and described by a two-band Bose-Hubbard model with generic one-body and two-body terms. By first projecting the system to
Externí odkaz:
http://arxiv.org/abs/2210.15408
Publikováno v:
Phys. Rev. A 106, 043315 (2022)
We study the bound states of $N$ identical bosons that are described by a multiband Bose-Hubbard model with generic hoppings and an attractive onsite interaction. Using a variational approach, we first derive exact integral equations for the dimers,
Externí odkaz:
http://arxiv.org/abs/2208.01429
Publikováno v:
Phys. Rev. A 106, 033304 (2022)
We start with a variational approach and derive a set of coupled integral equations for the bound states of $N$ identical spin-$\uparrow$ fermions and a single spin-$\downarrow$ fermion in a generic multiband Hubbard Hamiltonian with an attractive on
Externí odkaz:
http://arxiv.org/abs/2204.10003