HfO₂ shows the monoclinic phase at room temperature (RT), whereas the technologically important high-k tetragonal and cubic phases are observed at ∼1700 C and 2600 C, respectively. Herein, we reveal that the high-temperature cubic phase of HfO₂ is stabilized at RT after incorporating Dy and Sm codopant total concentration up to 13 at%. Below 13 at%, the monoclinic and cubic phases coexist, evidenced by Le-Bail profile refinement of the X-ray diffraction patterns. Transmission electron micrographs demonstrate average particle size as ∼31 and ∼10 nm for the monoclinic and cubic phase, respectively, which agrees with the crystallite size estimated from Debye–Scherrer equation. The monoclinic to cubic phase transformation is explained in terms of the oxygen vacancies formation and difference in ionic radii of Sm³⁺, Dy³⁺, and Hf⁴⁺ ions. Interestingly, electron spin resonance spectroscopy analysis indicates that while HfO₂ exhibits oxygen vacancies, Dy and Sm co-doped HfO₂ shows formation of magnetically inactive defect complexes. Moreover, low Dy and Sm co-dopant concentration in HfO₂ produces strong emissions in green, yellow, and orange-red color regions under different excitation wavelength induced via exchange of excited electrons between nearby energy levels of Dy³⁺ and Sm³⁺. Such a weak energy transfer phenomenon is primarily governed through multipolar interaction mechanism.

HfO ₂在室温 (RT) 下显示单斜相，而技术上重要的高k四方相和立方相分别在~1700 C 和 2600 C 下观察到。在此，我们揭示了 HfO ₂的高温立方相在加入 Dy 和 Sm 共掺杂剂总浓度高达 13 at% 后，在室温下稳定。低于 13 at%，单斜相和立方相共存，X 射线衍射图的 Le-Bail 轮廓细化证明了这一点。透射电子显微照片显示单斜晶相和立方晶相的平均粒径分别为~31 和~10 nm，这与根据 Debye-Scherrer 方程估计的微晶尺寸一致。从氧空位形成和 Sm ³⁺、Dy ³⁺和 Hf ⁴⁺离子的离子半径差异来解释单斜向立方相转变。有趣的是，电子自旋共振光谱分析表明，虽然 HfO ₂表现出氧空位，但 Dy 和 Sm 共掺杂的 HfO_图2显示了磁性非活性缺陷复合物的形成。此外，HfO _{2 中的}低 Dy 和 Sm 共掺杂剂浓度在通过 Dy ³⁺和 Sm ³⁺附近能级之间的激发电子交换诱导的不同激发波长下在绿色、黄色和橙红色区域产生强发射。这种弱能量转移现象主要是通过多极相互作用机制来控制的。