High-efficiency and dynamic stable electromagnetic wave attenuation for la doped bismuth ferrite at elevated temperature and gigahertz frequency

The immense potential of electromagnetic wave attenuation materials for applications in harsh dynamic environment has propelled much recent research and development. Here, we present the original observations on high-temperature electromagnetic properties and attenuation behavior of Bi_0.8La_0.2FeO₃ at 323-673 K. Bi_0.8La_0.2FeO₃ exhibits high-efficiency and stable attenuation at dynamic temperature and frequency conditions. With the increase of temperature, the attenuation capacity enhances, where the minimum reflection loss is less than -10 dB from 323 K to 673 K, and the best reflection loss reaches -54 dB at 573 K, which is 2.7 times that of BiFeO₃. With changing frequency, the effective reflection loss (≤-10 dB) almost covers 3 GHz in the full temperature range. The excellent attenuation capacity of Bi_0.8La_0.2FeO₃ is attributed to the crystal structure and electron structure due to the substitution of La, which enhances conductivity and natural ferromagnetic resonance, resulting in the enhancement of electromagnetic properties and improvement of electrical-magnetic synergy at elevated temperature. This work highlights the bismuth ferrite family as promising high-efficiency and stable electromagnetic wave attenuation materials.