Elastic stripes formation at metal-insulator transitions

We consider a general model of an electronic metal-insulator transition coupled to the elastic degrees of freedom of the lattice, and investigate the possibility of an emerging inhomogeneous phase, made by alternating stripes with metallic and insulating behavior, as the system crosses the transition. We solve the general elastic equations and minimize the total free energy of the system. We find that a stripe pattern may emerge for electronic transitions of either first order and second order. Stripes are stabilized when the typical elastic energy gained by forming the stripes overcomes the typical electronic and domain wall energy costs, and when they extend across the entire depth of the system. We also study the behavior of the metallic phase fraction as function of temperature across the spinodal region of a first order phase transition.