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Freezing and large time scales induced by geometrical frustration

Michel Ferrero·Federico Becca·Frédéric Mila
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Abstract

We investigate the properties of an effective Hamiltonian with competing interactions involving spin and chirality variables, relevant for the description of the {\it trimerized} version of the spin-1/2 {\it kagome} antiferromagnet. Using classical Monte Carlo simulations, we show that remarkable behaviors develop at very low temperatures. Through an {\it order by disorder} mechanism, the low-energy states are characterized by a dynamical freezing of the chiralities, which decouples the lattice into ``dimers'' and ``triangles'' of antiferromagnetically coupled spins. Under the presence of an external magnetic field, the particular topology of the chiralities induces a very slow spin dynamics, reminiscent of what happens in ordinary spin glasses.

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Michel Ferrero, Federico Becca, Frédéric Mila. 2003-06-30. Freezing and large time scales induced by geometrical frustration. https://doi.org/10.1103/physrevb.68.214431

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