Random field mechanism in the diluted J1-J2 model

The classical ferromagnetic Ising model in the presence of competing antiferromagnetic interactions hosts a very interesting phase diagram: At low temperatures and for g =|J₂|/ J₁<1/2 the system is in a ferromagnetic phase whereas for g>1/2 and at low temperatures a stripe phase obtains. At high temperature one finds the disordered paramagnetic phase for all values of $g$. We investigate the effects of site dilution on the various phases highlighted above for the clean J₁-J₂ model, and also analyze its impact on the intervening phase transitions. We show that the stripe phase is extremely susceptible to randomness very much in contrast to the ferromagnetic phase. The reasoning behind the extreme sensitivity of the stripe order to randomness will be highlighted during the talk. Impact of disorder on the nature of transition in this model and its universality class will also be discussed in this presentation.