English

On-chip detection of anisotropic thermopolarization in quartz

Materials Science 2026-05-19 v1

Abstract

Temperature gradients are widely used to drive and probe transport phenomena in solids, forming the basis of heat-to-charge conversion processes. In typical experiments, local heating is introduced to generate a temperature gradient, and the resulting electrical response is detected by separate electrodes. Such measurements usually regard heating purely as a source of thermal excitation. Here, we show that heating inherently generates mechanical stress through thermal expansion, which in turn produces measurable electrical signals via electromechanical coupling. Using quartz as a model piezoelectric system, we demonstrate that heat can be converted to electrical currents via thermally generated stress. The on-chip device used in our experiment enables us to probe the anisotropy of the piezoelectric tensor through the thermally generated current, exhibiting twofold and threefold responses for X-cut and Z-cut crystals, respectively. We further show that the response can be detected in both current and voltage modes. These results reveal a thermomechanical pathway for heat-to-charge conversion and establish a general platform for electrically probing thermomechanical responses in insulating materials.

Keywords

Cite

@article{arxiv.2605.17226,
  title  = {On-chip detection of anisotropic thermopolarization in quartz},
  author = {Shuichi Iwakiri and Yasumitsu Miyata and Takao Mori},
  journal= {arXiv preprint arXiv:2605.17226},
  year   = {2026}
}