Using high-precision Monte-Carlo simulations based on a parallel version of the Wang-Landau algorithm and finite-size scaling we study the effect of quenched disorder in the crystal-field coupling of the Blume-Capel model on the square lattice. The first-order transition for large crystal-field coupling is softened to become continuous, with a divergent correlation length. A scaling analysis of the correlation length as well as the susceptibility, magnetization, and specific heat reveals that it belongs to the universality class of the Ising model with additional logarithmic corrections which is also observed for the Ising model itself if coupled to weak disorder. Our results are in agreement with an early real-space renormalization-group study of the model as well as a very recent numerical work where quenched randomness was introduced in the exchange coupling.
|Number of pages||8|
|Journal||Physical Review E|
|Publication status||Submitted - 24 Jul 2020|