Random Spin-1 Quantum Chains

نویسندگان

  • Beatriz Boechat
  • Andreia Saguia
چکیده

We study disordered spin-1 quantum chains with random exchange and biquadratic interactions using a real space renormalization group approach. We find that the dimerized phase of the pure biquadratic model is unstable and gives rise to a random singlet phase in the presence of weak disorder. In the Haldane region of the phase diagram we obtain a quite different behavior.

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تاریخ انتشار 1996