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Effects of Random Biquadratic Couplings in a Spin-1 Spin-Glass Model

J. M. de Araujo·F. A. da Costa·F. D. Nobre
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Abstract

A spin-1 model, appropriated to study the competition between bilinear (J_{ij}S_{i}S_{j}) and biquadratic (K_{ij}S_{i}^{2}S_{j}^{2}) random interactions, both of them with zero mean, is investigated. The interactions are infinite-ranged and the replica method is employed. Within the replica-symmetric assumption, the system presents two phases, namely, paramagnetic and spin-glass, separated by a continuous transition line. The stability analysis of the replica-symmetric solution yields, besides the usual instability associated with the spin-glass ordering, a new phase due to the random biquadratic couplings between the spins.

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J. M. de Araujo, F. A. da Costa, F. D. Nobre. 2000-05-01. Effects of Random Biquadratic Couplings in a Spin-1 Spin-Glass Model. https://doi.org/10.1007/s100510051076

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