{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,10]],"date-time":"2026-05-10T00:23:50Z","timestamp":1778372630721,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,10,25]],"date-time":"2017-10-25T00:00:00Z","timestamp":1508889600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Grants Council of the HKSAR Government","award":["522813"],"award-info":[{"award-number":["522813"]}]},{"name":"Innovation and Technology Commission of the HKSAR Government to the Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center","award":["1-BBYW"],"award-info":[{"award-number":["1-BBYW"]}]},{"name":"Postgraduate Studentship of The Hong Kong Polytechnic University","award":["RTUY"],"award-info":[{"award-number":["RTUY"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We report, theoretically and experimentally, the realization of a high detection performance in a novel magnetoelectric (ME) transverse gradient sensor based on the large ME effect and the magnetic field gradient (MFG) technique in a pair of magnetically-biased, electrically-shielded, and mechanically-enclosed ME composites having a transverse orientation and an axial separation. The output voltage of the gradient sensor is directly obtained from the transverse MFG-induced difference in ME voltage between the two ME composites and is calibrated against transverse MFGs to give a high detection sensitivity of 0.4\u201330.6 V\/(T\/m), a strong common-mode magnetic field noise rejection rate of &lt;\u221214.5 dB, a small input-output nonlinearity of &lt;10 ppm, and a low gradient noise of 0.16\u2013620 nT\/m\/      Hz       in a broad frequency range of 1 Hz\u2013170 kHz under a small baseline of 35 mm. An analysis of experimental gradient noise spectra obtained in a magnetically-unshielded laboratory environment reveals the domination of the pink (1\/f) noise, dielectric loss noise, and power-frequency noise below 3 kHz, in addition to the circuit noise above 3 kHz, in the gradient sensor. The high detection performance, together with the added merit of passive and direct ME conversion by the large ME effect in the ME composites, makes the gradient sensor suitable for the passive, direct, and broadband detection of transverse MFGs.<\/jats:p>","DOI":"10.3390\/s17112446","type":"journal-article","created":{"date-parts":[[2017,10,25]],"date-time":"2017-10-25T11:13:27Z","timestamp":1508930007000},"page":"2446","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Magnetoelectric Transverse Gradient Sensor with High Detection Sensitivity and Low Gradient Noise"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9531-5862","authenticated-orcid":false,"given":"Mingji","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"},{"name":"Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2536-5658","authenticated-orcid":false,"given":"Siu","family":"Or","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China"},{"name":"Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TMAG.2014.2320361","article-title":"Inversion of geo-magnetic SQUID gradiometer prospection data using polyhedral model interpretation of elongated anomalies","volume":"50","author":"Schneider","year":"2014","journal-title":"IEEE Trans. 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