Dielectric constant at x-band microwave frequencies for multiferroic BiFeO3 thin films.

The magnetic-induced dielectric responses of BiFeO₃ (BFO) thin films were measured at the X-band microwave frequency ranged from 7 to 12.5 GHz. The measurement was given initially by a high-precision cavity microwave resonator without magnetic field. Both the real and imaginary parts of the permittivity showed its dielectric property as a function of the measuring frequency. The X-band dielectric responses of the BFO thin film were then measured by a controlled magnetic field at room temperature. The data demonstrated up to 2.2% dielectric tunability by using only 3.46 kOe magnetic field at TE₁₀₇ mode (9.97705 GHz). [ABSTRACT FROM AUTHOR]