Spin reduction transition in spin - 32 random Heisenberg chains
نویسندگان
چکیده
Random spin3 2 antiferromagnetic Heisenberg chains are investigated using an asymptotically exact renormalization group. Randomness is found to induce a quantum phase transition between two random-singlet phases. In the strong randomness phase the effective spins at low energies are Se f f5 3 2 , while in the weak randomness phase the effective spins are Se f f5 1 2 . Separating them is a quantum critical point near which there is a nontrivial mixture of spin1 2 , spin-1, and spin3 2 effective spins at low temperatures.
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