28 citations · 81 across the 19 of their papers we have counts for
19 papers
Ground state energy of the dilute Bose-Hubbard gas on Bravais lattices
Norbert Mokrzański, Marcin Napiórkowski, Jacek Wojtkiewicz
We study interacting bosons on a three-dimensional Bravais lattice with positive hopping amplitudes and on-site repulsive interactions. We prove that, in the dilute limit ,…
Third order corrections to the ground state energy of the gas of spin fermions with arbitrary densities of different spin projections
Piotr H. Chankowski, Jacek Wojtkiewicz, Szymon Augustynowicz
Recently we have computed the third order corrections to the ground state energy of the arbitrarily polarized diluted gas of spin 1/2 fermions interacting through a spin-independen…
Long-range order in the XY model on the honeycomb lattice
Jacek Wojtkiewicz, Krzysztof Wohlfeld, Andrzej M. Oleś
Using the reflection positivity method we provide the rigorous proof of the existence of long range magnetic order for the XY model on the honeycomb lattice for large spins $S\ge 2…
Ground state energies of the Hubbard models and the Hartree Fock approximation
Jacek Wojtkiewicz, Piotr H. Chankowski
According to the `folk knowledge', the Hartree-Fock (H-F) approximation applied to the Hubbard model becomes exact in the limit of small coupling (the smaller , the better…
Third order corrections to the ground state energy of the polarized diluted gas of spin fermions
Piotr H. Chankowski, Jacek Wojtkiewicz, Rashad Bakhshizada
We present the results of the computation of the third order corrections to the ground state energy of the diluted polarized gas of nonrelativistic spin fermions interacting…
On the ground-state energy of a mixture of two different oppositely polarized fermionic gases
Piotr Chankowski, Jacek Wojtkiewicz
We report the results of the computation of the order correction, where is the Fermi wave vector and the -wave scattering length of th…