Effect of non-magnetic dilution in <b> </b>: A composite system of spin-1/2 triangular Heisenberg-like and honeycomb Ising-like antiferromagnets

Abstract We report the evolution of the magnetic state in Ba 2 CoTeO 6 with magnetic Co 2+ substituted by non-magnetic Zn 2+ . Ba 2 CoTeO 6 , a strongly frustrated antiferromagnet which consists of two highly frustrated subsystems, undergoes two antiferromagnetic transitions at 12 K and 3 K, respectively. The magnetization and specific heat measurements demonstrate that the antiferromagnetic transition at in the parent compound Ba 2 CoTeO 6 is drastically suppressed with Zn/Co substitution. On the other hand, with the increasing of Zn doping level x , the antiferromagnetic ordering below in Ba 2 CoTeO 6 firstly becomes a spin glass state, and eventually transforms into a spin disordered state at higher Zn concentration x = 0.6. Our results indicate that magnetic site dilution by Zn/Co substitution is an effective approach to induce the novel disordered state in Ba 2 CoTeO 6 .