Switchable voltage offset in a Heusler alloy-based magnetic tunnel junction

Wanjun Park, Kyungsun Moon

Research output: Contribution to journalArticle

Abstract

We investigate the tunneling magnetoresistance (TMR) of the magnetic tunnel junction (MTJ) comprised of the Heusler alloy (Co2MnSi) and the pinned CoFe to probe the spin polarization of Co2MnSi. From the TMR value thus obtained, we estimate 40% polarization of Co2MnSi, much less than 100% expected for the suspected half metal. Remarkably, upon applying the weak switching magnetic field to the MTJ in the parallel state, our system exhibits a finite open-circuit voltage on the order of several 10μV in the anti-parallel state. We have demonstrated that the reversal of magnetic dipolar field induced by the Heusler alloy as a free layer can generate an electromotive force of the same order and can clearly explain the observed polarity and sample size dependence of the voltage offset at zero bias current.

Original languageEnglish
Pages (from-to)274-278
Number of pages5
JournalJournal of Magnetism and Magnetic Materials
Volume469
DOIs
StatePublished - 2019 Jan 1

Fingerprint

Tunnelling magnetoresistance
Tunnel junctions
tunnel junctions
Magnetic fields
Electromotive force
Spin polarization
electromotive forces
Bias currents
Electric potential
electric potential
Open circuit voltage
polarization
open circuit voltage
polarity
Metals
Polarization
probes
estimates
magnetic fields
metals

Keywords

  • Half metal
  • Heusler alloy
  • Magnetic tunnel junction
  • Voltage offset

Cite this

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Switchable voltage offset in a Heusler alloy-based magnetic tunnel junction. / Park, Wanjun; Moon, Kyungsun.

In: Journal of Magnetism and Magnetic Materials, Vol. 469, 01.01.2019, p. 274-278.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Switchable voltage offset in a Heusler alloy-based magnetic tunnel junction

AU - Park, Wanjun

AU - Moon, Kyungsun

PY - 2019/1/1

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AB - We investigate the tunneling magnetoresistance (TMR) of the magnetic tunnel junction (MTJ) comprised of the Heusler alloy (Co2MnSi) and the pinned CoFe to probe the spin polarization of Co2MnSi. From the TMR value thus obtained, we estimate 40% polarization of Co2MnSi, much less than 100% expected for the suspected half metal. Remarkably, upon applying the weak switching magnetic field to the MTJ in the parallel state, our system exhibits a finite open-circuit voltage on the order of several 10μV in the anti-parallel state. We have demonstrated that the reversal of magnetic dipolar field induced by the Heusler alloy as a free layer can generate an electromotive force of the same order and can clearly explain the observed polarity and sample size dependence of the voltage offset at zero bias current.

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