Effect of thermal annealing and compression on the stability of microwrinkle patterns.

We find that annealing followed by uniaxial compression affects the microwrinkle pattern, which originally shows a complex stripe phase, and its stability to mechanical perturbation. We observe a characteristic quasi-biaxial stripe pattern after unloading compressive stress in contrast to the case without annealing, which shows the retrieval of the original pattern. Moreover, another loading-unloading cycle in a different direction induces a change in the modulated pattern, indicating that the pattern is no longer stable to mechanical perturbations.