Stripes and thet-JModel

We investigate the two-dimensional t-J model at a hole doping of $x=\frac{1}{8}$. The low-energy states are uniform (not striped). We find numerous excited states with charge density wave structures, which may be interpreted as striped phases. Some of these are consistent with neutron scattering data on cuprates and nickelates. Without additional terms in the t-J Hamiltonian, stripes can be stabilized only as ground states through the application of artificial boundary conditions.