  We discuss a possibility to control a heat conductivity in simple
one-dimensional models of dielectrics by means of external mechanical loads. To
illustrate such possibilities we consider first a well-studied chain with
degenerate double-well potential of the interparticle interaction. Contrary to
previous studies, we consider varying length of the chain with fixed number of
particles. Number of possible energetically degenerate ground states strongly
depends on the overall length of the chain, or, in other terms, on average
length of the link between neighboring particles. These degenerate states
correspond to mechanical equilibrium, therefore one can say that the transition
between them mimics to some extent a process of plastic deformation. We
demonstrate that such modification of the chain length can lead to quite
profound (almost five-fold) reduction of the heat conduction coefficient. Even
more profound effect is revealed for a model with single-well non-convex
potential. It is demonstrated that in certain range of constant external
forcing this model becomes "effectively"\ double-well, and has a multitude of
possible states of equilibrium for the same value of the external load. Thus,
the heat conduction coefficient can be reduced by two orders of magnitude. We
suggest a mechanical model of a chain with periodic double-well potential,
which allows control over the heat conduction. The models considered may be
useful for description of heat transport in biological macromolecules and for
control of the heat transport in microsystems.
