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The indirect and direct magnetoelectric (ME) couplings of electrically poled and unpoled P(VDF-HFP)/ CoFe 2 O 4 nanofiber composite films are studied through vibrating-sample magnetometer analysis and magnetodielectric measurements, respectively. In the presence of a magnetic field, the electrical order parameters such as dielectric constant, dielectric loss, capacitance, and impedance are found to change. Also, the percentages of magnetodielectric constant, magnetoloss, magnetocapacitance, and magnetoimpedance are calculated for the composite films with different loadings of CoFe 2 O 4 nanofibers. The Landau free-energy theory is used to examine the nature of ME coupling in the composite films, and the results reveal the existence of biquadratic (P 2 M 2 ) coupling in all of the unpoled and poled films. Moreover, the higher-order ME coupling coefficient of composite films is examined, and the highest values are found to be 1.74 × 10 −4 and 2.24 × 10 −4 , respectively, for unpoled and poled films of 5 wt % P(VDF-HFP)/CoFe 2 O 4 nanofibers. The prepared films with strong ME coupling can be used in device applications such as tunable filters, magnetic sensors, and transducing devices.

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