Why do stripes form in doped antiferromagnets and what is their relationship to superconductivity?

Experiments show evidence for stripe formation in the underdoped cuprates. Here we discuss recent numerical calculations on the t-J model which tell us about the mechanism responsible for stripe formation and the relationship between stripes and superconductivity. PACS Numbers: 74.20.Mn, 71.10.Fd, 71.10.Pm It is clear from a variety of experiments that stripes appear as important low-energy configurations in the underdoped cuprates. However, the basic questions of why stripes form and what role they play in superconductivity remain controversial. A decade ago Hartree-Fock solutions of the Hubbard model showed that stripes—one-dimensional domains of increased hole density forming anti-phase Néel boundaries—were present in mean field solutions of the Hubbard model. Here the stability of the stripe structure arises from the reduction in kinetic energy that the holes experience in moving transverse to the stripes. However, the stripes in the Hartree-Fock solution are characterized by a filling of one hole per domain wall unit cell, while experiments on the cuprates at low doping find a filling of half this. In addition, within the Hartree-Fock framework, it is not clear how superconductivity enters. An alternative view argues that stripe formation arises from competition between phase