Magnetic equation of state of the randomly diluted Ising dipolar-coupled ferromagnet LiTb 0.9Y 0.1F 4

The magnetic equation of state of the randomly diluted uniaxial dipolar-coupled ferromagnet LiTb _0.9Y _0.1F ₄ has been measured using a SQUID magnetometer. It was found that both a random and a random-nonuniversal equation of state predicted for the random Ising dipolar-coupled ferromagnet provide comparable fits to the data. These measurements represent the first determination of the equation of state of a random system at marginal dimensionality.