Exact solution of a one-dimensionalXYmodel in a random field

We present an exact solution of a one-dimensional $\mathrm{XY}$ model in a random magnetic field in the limit of strong-field pinning. The structure factor exhibits Lorentzian-squared behavior at nonzero temperatures. The scaling behavior of the correlation length as a function of randomness is different from that obtained in the weak-field pinning regime. We also study the dynamical behavior of the system using a simple relaxational model. The magnetization decays anomalously with time as $t^{\frac{7}{6}}{e}^{{-ct}^{\frac{1}{3}}}$.