Design of the vanadium dioxide temperature self-regulator in the terahertz regime

Abstract

A temperature self-regulator can keep the particle temperature almost constant over a wide range of light intensities. In this study, we propose a temperature self-regulator design under terahertz radiation. A key ingredient in this proposal is vanadium dioxide (VO$_2$), whose properties in the terahertz regime vary drastically around its phase transition temperature. One would expect that the particle temperature may be self-adjusted in the phase change process. To verify this notion, we employ the Mie theory for the theoretical analysis. The results show that the absorption exhibits nonlinear dependence with different parameters. At optimized sizes, the absorption of terahertz radiation can be significantly suppressed once the phase change occurs. Consequently, the temperature does not show a significant increment with increasing intensity. These results can facilitate the future development of temperature self-regulator using phase change materials in the terahertz regime.