Transition rates via Bethe ansatz for the spin-½ Heisenberg chain

Abstract

We use the exact determinantal representation derived by Kitanine, Maillet,\nand Terras for matrix elements of local spin operators between Bethe wave\nfunctions of the one-dimensional s=1/2 Heisenberg model to calculate and\nnumerically evaluate transition rates pertaining to dynamic spin structure\nfactors. For real solutions z_1,...,z_r of the Bethe ansatz equations, the size\nof the determinants is of order r x r. We present applications to the\nzero-temperature spin fluctuations parallel and perpendicular to an external\nmagnetic field.\n