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Giant and Linear Magnetoresistance in Liquid Metals at Ambient Temperature

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 نشر من قبل Xiaolin Wang
 تاريخ النشر 2019
  مجال البحث فيزياء
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Disorder-induced magnetoresistance has been reported in a range of solid metals and semiconductors, however, the underlying physical mechanism is still under debate because it is difficult to experimentally control. Liquid metals, due to lack of long-range order, offers an ideal model system where many forms of disorder can be deactivated by freezing the liquid. Here we report non-saturating magnetoresistance discovered in the liquid state of three metals: Ga, Ga-In-Sn and Bi-Pb-Sn-In alloys. The giant magnetoresistance appears above the respective melting points and has a maximum of 2500% at 14 Tesla. The reduced diamagnetism in the liquid state implies that a short-mean free path of the electron, induced by the spatial distribution of the liquid structure, is a key factor. A potential technological merit of this liquidtronic magnetoresistance is that it naturally operates at higher temperatures.

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