High SNR magnetoelectric sensor with dual working modes for wideband magnetic field detection

Magnetoelectric (ME) composites exhibit extremely high sensitivity for magnetic field at the fixed resonant frequency, due to the strong strain-mediated ME coupling. However, wideband magnetic field detection is still challenging, as the ME coefficient depends strongly on the frequency. In this work, we propose a magnetoelectric sensor composed of three ME units in series/parallel connections, which works at dual modes to extend the frequency range with high signal-to-noise ratio (SNR). The SNR is enhanced by about 22.68 dB and the bandwidth is broadened from 100 Hz to 1 kHz, with a high sensitivity for frequency conversion mode by series/parallel connections. Limits of detections (LoDs) as low as 207 pT and 460 pT are demonstrated at 1000 Hz and 100 kHz, respectively, showing promising applications in wideband magnetic field detection.