Nonlinear spin dynamics of dilute He-3-He-4 at very high B/T

We are conducting an experimental search for spin-diffusion anisotropy in d ilute He-3-He-4 mixtures at very high B/T (17 T, 2 mK). Previous experiment s have not reached sufficiently high B/T ratios to observe the effect in ve ry dilute mixtures, for which quantitative theoretical predictions exist. T he planned experiments will require NMR experiments at very high values of the dimensionless spin rotation parameter mu M. We have performed numerical simulations of the nonlinear spin dynamics to assess the feasibility of sp in-wave and spin-echo experiments. (C) 2000 Elsevier Science B.V. All right s reserved.