Oscillatory Caloric Cooling Below the Curie Temperature in Ordered Materials

Solid-state cooling technologies based on caloric effects typically rely on quasi-static field variations near the Curie temperature, where entropy changes are maximized. Here we demonstrate a fundamentally different mechanism: an oscillatory caloric effect operating strictly below the Curie temperature, in the ordered phase of a ferroelectric material. By driving the polarization through controlled oscillations, we induce periodic entropy modulation that extracts heat from the material without requiring proximity to a phase transition. We further show that part of the oscillatory electrical energy can be recovered through a resonant transfer network, enabling cooling efficiencies reaching 20–25% of the Carnot limit without energy recovery and theoretically exceeding 50% with optimized resonant coupling. Finally, we generalize the mechanism to ferromagnetic materials below their magnetic Curie point, suggesting a broader class of oscillatory caloric phenomena in ordered systems. These results open a new direction for high-efficiency, environmentally friendly cooling technologies with applications in microelectronics, artificial intelligence, and solar-powered refrigeration.