J un 1 99 6 A Frenkel - Kontorova Model with Two Spring Constants : New Phase and Phase transition
نویسنده
چکیده
A discrete Frenkel-Kontorova model with two alternate spring constants k1 and k2 is studied in detail. It is found that this model has a lots of surprising behaviors. The continuum version of this model is different from the sine-Gordon equation, which is the continuum version of the standard FK model. More interestingly, it has an unpinned commensurate phase which is translationally invariant and has a zero-frequency phonon mode. The model has a phase transition on phase space points, which form a square lattice determined by the two non-zero and non-negative solutions of the equation sin(2πx) = 0. Besides, we predict there is another more interesting phase transition of the unlocked commensurate phase which may break translational invariance, as the strength of the substrate potential is increased. PACS numbers: 05.50.+q, 0.5.70 Fh, 05.70.Jk
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Se p 19 96 A Frenkel - Kontorova Model with Two Spring Constants : New Phases and Phase Transitions
A discrete Frenkel-Kontorova model with two alternate spring constants k1 and k2 is studied. It is found that this model has many surprising behaviours. The continuum version of this model is different from the sine-Gordon equation, the continuum version of the standard FK model. More interestingly, it has an unpinned commensurate phase which is translationally invariant. A phase transition tak...
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