Holes in a two-dimensional Hubbard antiferromagnet

Single-hole properties in thet-Jand strong-coupling models

“…The single-hole properties in the t-J and strongcoupling models have been studied previously, the first having received more attention. Methods include exactdiagonalization studies of small lattices [7][8][9][10][11][12][13][14] , studies of infinite lattices using a restricted basis set 4,5,[15][16][17][18] , Monte-Carlo methods [19][20][21][22][23][24][25] , and other methods [26][27][28][29][30][31][32][33][34] . Properties discussed include the ground-state energy, the bandwidth, the dispersion, the band masses, the nearestneighbor spin-spin correlations and the spectral function.…”

The Spectrum of Four-Point Hubbard Model with Holes

“…Hi describes the next-neighbour (nnn) hopping of the order of t 2 /U with and without a spin-flip process, where (ij) and (jk) are nearest neighbours. Both parts of the Hamiltonian define the t -t' -J model (with t' = t 2 /[/)t 3 ' 4 l. Some numerical studies are done for such t -t' -J model^5' 6 ' but there is only a few analytic results. The purpose of this paper is to deal with such models for small system in order to obtain the analytic results and compare them with each other.…”

The Structure of Energy Matrix and the Ground State for Two-Dimensional Hubbard Model

“…The ground state of two-dimensional (2D) U -oo Hubbard model with band occupation less than 0.5 has been a topic of much concern recently.t [1][2][3][4][5][6][7][8] ! The data of numerical calculations by exact diagonalization method for small clusters as large as 4 x 4 sites show that Nagaoka state is unstable.…”