Polyacetylene and Relativistic Field Theory Models

Solitons in polyacetylene and relativistic-field-theory models

Using recent results on a model relativistic field theory, we find explicitly a new solitonlike solution, essentially the conventional strong polaron, in the continuum interacting electronphonon model of a Peierls-dimerized chain such as polyacetylene [(CH}„].This solution is in good agreement with recent numerical simulations in a discrete model of (CH)„. %e discuss further areas in which know...

Soliton Excitations in Polyacetylene and Relativistic Field Theory Models*

A continuum model of a Peierls-dimerized chain, as described generally by Brazovskii and discussed for the case of polyacetylene by Takayama, Lin-Liu and Maki (TLM), is considered. The continuum (Bogliubov-de Gennes) equations arising in this model of interacting electrons and phonons are shown to be equivalent to the static, semiclassical equations for a solvable model field theory of self-cou...

Relativistic Quantum Field Theory

Mean-field theory for alkali-metal-doped polyacetylene.

The Landau theory used by Choi and Mele (CM) to treat their rotor model on a triangular lattice for the orientational ordering of polyacetylene chains in alkali-metal-doped polyacetylene is studied. A reanalysis of the higher-order terms in the Landau expansion indicates that cosine ordering can support a nonzero cubic term in the Landau expansion whereas the sine-ordered phase has no such term...

Relativistic superfluid hydrodynamics from field theory

It is well known that the hydrodynamics of a zero-temperature superfluid can be formulated in field-theoretic terms, relating for example the superfluid four-velocity to the gradient of the phase of a Bose-condensed scalar field. At nonzero temperatures, where the phenomenology of a superfluid is usually described within a two-fluid picture, this relationship is less obvious. For the case of a ...