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Four-state ferroelectric spin-valve.

ABSTRACT: Spin-valves had empowered the giant magnetoresistance (GMR) devices to have memory. The insertion of thin antiferromagnetic (AFM) films allowed two stable magnetic field-induced switchable resistance states persisting in remanence. In this letter, we show that, without the deliberate introduction of such an AFM layer, this functionality is transferred to multiferroic tunnel junctions (MFTJ) allowing us to create a four-state resistive memory device. We observed that the ferroelectric/ferromagnetic interface plays a crucial role in the stabilization of the exchange bias, which ultimately leads to four robust electro tunnel electro resistance (TER) and tunnel magneto resistance (TMR) states in the junction.

SUBMITTER: Quindeau A

PROVIDER: S-EPMC4426701 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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Four-state ferroelectric spin-valve.

Quindeau Andy A Fina Ignasi I Marti Xavi X Apachitei Geanina G Ferrer Pilar P Nicklin Chris C Pippel Eckhard E Hesse Dietrich D Alexe Marin M

Scientific reports 20150511

Spin-valves had empowered the giant magnetoresistance (GMR) devices to have memory. The insertion of thin antiferromagnetic (AFM) films allowed two stable magnetic field-induced switchable resistance states persisting in remanence. In this letter, we show that, without the deliberate introduction of such an AFM layer, this functionality is transferred to multiferroic tunnel junctions (MFTJ) allowing us to create a four-state resistive memory device. We observed that the ferroelectric/ferromagnet ...[more]

PMID: 25961513

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