Abstract We investigate properties of spin-imbalanced ultracold Fermi gas in a large range of spin polarizations at low temperatures. We present results of microscopic calculations based on mean-field and density functional theory approaches, with no symmetry constraints. At low polarization values we predict the structure of the system as consisting of several spin-polarized droplets. As the polarization increases, the system self-organizes into a disordered structures similar to liquid crystals, and energetically they can compete with ordered structures such as grid-like domain walls. At higher polarizations the system starts to develop regularities that, in principle, can be called supersolid, where periodic density modulation and pairing correlations coexist. The robustness of the results has been checked with respect to temperature effects, dimensionality, and the presence of a trapping potential. Dynamical stability has also been investigated.Abstract We investigate properties of spin-imbalanced ultracold Fermi gas in a large range of spin polarizations at low temperatures. We present results of microscopic calculations based on mean-field and density functional theory approaches, with no symmetry constraints. At low polarization values we predict the structure of the system as consisting of several spin-polarized droplets. As the polarization increases, the system self-organizes into a disordered structures similar to liquid crystals, and energetically they can compete with ordered structures such as grid-like domain walls. At higher polarizations the system starts to develop regularities that, in principle, can be called supersolid, where periodic density modulation and pairing correlations coexist. The robustness of the results has been checked with respect to temperature effects, dimensionality, and the presence of a trapping potential. Dynamical stability has also been investigated.

arXiv:2211.01055New Journal of PhysicsMar 1, 202311 citations

Phase diagram and dynamics simulations of two-dimensional spin clusters

Philippe Depondt, Franz, Mertens, G.

Jan 1, 20090 citations

Spin Structures of the Hubbard Clusters and the Pseudogap

M. Ya. Ovchinnikova

Journal of Superconductivity and Novel MagnetismMay 2, 20132 citations

Self-organized three-band structure of the doped fermionic Ising spin glass

Heiko Feldmann, R. Oppermann

The fermionic Ising spin glass is analyzed for arbitrary filling and for all temperatures. A self-organized three-band structure of the model is obtained in the magnetically ordered phase. Deviation from half-filling generates a central nonmagnetic band, which becomes sharply separated at $T=0$ by (pseudo)gaps from upper and lower magnetic bands. Replica symmetry breaking effects are derived for several observables and correlations. They determine the shape of the three-band density of states, and, for given chemical potential, influence the fermion filling strongly in the low-temperature regime.The fermionic Ising spin glass is analyzed for arbitrary filling and for all temperatures. A self-organized three-band structure of the model is obtained in the magnetically ordered phase. Deviation from half-filling generates a central nonmagnetic band, which becomes sharply separated at $T=0$ by (pseudo)gaps from upper and lower magnetic bands. Replica symmetry breaking effects are derived for several observables and correlations. They determine the shape of the three-band density of states, and, for given chemical potential, influence the fermion filling strongly in the low-temperature regime.

arXiv:cond-mat/9910119Physical review. B, Condensed matterOct 1, 20006 citations

Extending GPU-accelerated Gaussian integrals in the TeraChem software package to f type orbitals: Implementation and applications

Yuanheng Wang, Diptarka Hait, Katherine Grace Johnson +4 more

The increasing availability of graphics processing units (GPUs) for scientific computing has prompted interest in accelerating quantum chemical calculations through their use. However, the complexity of integral kernels for high angular momentum basis functions often limits the utility of GPU implementations with large basis sets or for metal containing systems. In this work, we report the implementation of f function support in the GPU-accelerated TeraChem software package through the development of efficient kernels for the evaluation of Hamiltonian integrals. The high efficiency of the resulting code is demonstrated through density functional theory (DFT) calculations on increasingly large organic molecules and transition metal complexes, as well as coupled cluster singles and doubles calculations on water clusters. Preliminary investigations into Ni(I) catalysis with DFT and the photochemistry of MnH(CH3) with complete active space self-consistent field are also carried out. Overall, our GPU-accelerated software appears to be well-suited for fast simulation of large transition metal containing systems, as well as organic molecules.The increasing availability of graphics processing units (GPUs) for scientific computing has prompted interest in accelerating quantum chemical calculations through their use. However, the complexity of integral kernels for high angular momentum basis functions often limits the utility of GPU implementations with large basis sets or for metal containing systems. In this work, we report the implementation of f function support in the GPU-accelerated TeraChem software package through the development of efficient kernels for the evaluation of Hamiltonian integrals. The high efficiency of the resulting code is demonstrated through density functional theory (DFT) calculations on increasingly large organic molecules and transition metal complexes, as well as coupled cluster singles and doubles calculations on water clusters. Preliminary investigations into Ni(I) catalysis with DFT and the photochemistry of MnH(CH3) with complete active space self-consistent field are also carried out. Overall, our GPU-accelerated software appears to be well-suited for fast simulation of large transition metal containing systems, as well as organic molecules.

arXiv:2406.14920The Journal of Chemical PhysicsNov 6, 202419 citations

Spin Stability of Small Atomic Clusters

C.H. Dasso, A. Vitturi

Jan 1, 19940 citations

T=0

by (pseudo)gaps from upper and lower magnetic bands. Replica symmetry breaking effects are derived for several observables and correlations. They determine the shape of the three-band density of states, and, for given chemical potential, influence the fermion filling strongly in the low-temperature regime.