Voltage-controlled inversion of tunnel magnetoresistance in epitaxial nickel/graphene/MgO/cobalt junctions

Godel, Florian; Kamalakar, M. Venkata; Doudin, B.; Henry, Y.; Halley, D.; Dayen, Jean‐François

doi:10.1063/1.4898587

Cited by 54 publications

(53 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3 While its exact origin is still under study, 24 the increase of spin polarization with the number of layer is in agreement with the reported predictions of Karpan et al 25 and more recently Laczic et al 26 We note that the observed negative sign of the magneto-resistance and its amplitude has been observed reproducibly.…”

supporting

confidence: 79%

Protecting nickel with graphene spin-filtering membranes: A single layer is enough

Martin

Dlubak

Weatherup

et al. 2015

Applied Physics Letters

View full text Add to dashboard Cite

We report on the demonstration of ferromagnetic spin injectors for spintronics which are protected against oxidation through passivation by a single layer of graphene. The graphene monolayer is directly grown by catalytic chemical vapor deposition on pre-patterned nickel electrodes. X-ray photoelectron spectroscopy reveals that even with its monoatomic thickness, monolayer graphene still efficiently protects spin sources against oxidation in ambient air. The resulting single layer passivated electrodes are integrated into spin valves and demonstrated to act as spin polarizers. Strikingly, the atom-thick graphene layer is shown to be sufficient to induce a characteristic spin filtering effect evidenced through the sign reversal of the measured magnetoresistance.

show abstract

supporting

confidence: 79%

Protecting nickel with graphene spin-filtering membranes: A single layer is enough

Martin

Dlubak

Weatherup

et al. 2015

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…Spin filtering across a 2D material was first theoretically proposed by Karpan et al 143,144 , who predicted that graphene or graphite on lattice matched surfaces of nickel or cobalt behaves like a half-metal and can be used to inject 100% spin polarized current in to nonmagnetic conductors. Rather low values of magnetoresistance were found experimentally due to disorder at FM/graphene interface [145][146][147][148] . Thereafter, it was predicted that due to almost perfectly matched in-plane lattice constants of graphene and hBN, a FM/fewlayergraphene/hBN junction can act as an ideal spin filter with an increased R c A product [149][150][151] , which is essential for avoiding the conductivity mismatch problem for efficient spin injection in graphene 152 .…”

Section: B Spin Filtering Across Hbn/graphene Interfacementioning

confidence: 97%

Electrical spin injection, transport, and detection in graphene-hexagonal boron nitride van der Waals heterostructures: progress and perspectives

2018

View full text Add to dashboard Cite

The current research in graphene spintronics strives for achieving a long spin lifetime, and efficient spin injection and detection in graphene. In this article, we review how hexagonal boron nitride (hBN) has evolved as a crucial substrate, as an encapsulation layer, and as a tunnel barrier for manipulation and control of spin lifetimes and spin injection/detection polarizations in graphene spin valve devices. First, we give an overview of the challenges due to conventional SiO2 substrate for spin transport in graphene followed by the progress made in hBN based graphene heterostructures. Then we discuss in detail the shortcomings and developments in using conventional oxide tunnel barriers for spin injection into graphene followed by introducing the recent advancements in using the crystalline single/bi/tri-layer hBN tunnel barriers for an improved spin injection and detection which also can facilitate two-terminal spin valve and Hanle measurements, at room temperature, and are of technological importance. A special case of bias induced spin polarization of contacts with exfoliated and chemical vapour deposition (CVD) grown hBN tunnel barriers is also discussed. Further, we give our perspectives on utilizing graphene-hBN heterostructures for future developments in graphene spintronics.

show abstract

“…Recently, graphene has been explored as a barrier for spin transport, where TMR and spin filtering effects have been observed [9][10][11][12][13][14][15][16][17][18][19], including the bias dependence of the TMR [20]. However, the absence of a bandgap in semi-metallic and low resistive graphene has led to an increasing demand for an insulating 2D crystal [7][8][9].…”

Section: Introductionmentioning

confidence: 97%

Tunnel magnetoresistance with atomically thin two-dimensional hexagonal boron nitride barriers

et al. 2014

Self Cite

View full text Add to dashboard Cite

The two-dimensional atomically thin insulator hexagonal boron nitride (h-BN) constitutes a new paradigm in tunnel based devices. A large band gap, along with its atomically flat nature without dangling bonds or interface trap states, makes it an ideal candidate for tunnel spin transport in spintronic devices. Here, we demonstrate the tunneling of spin-polarized electrons through large area monolayer h-BN prepared by chemical vapor deposition in magnetic tunnel junctions. In ferromagnet/h-BN/ferromagnet heterostructures fabricated on a chip scale, we show tunnel magnetoresistance at room temperature. Measurements at different bias voltages and on multiple devices with different ferromagnetic electrodes establish the spin polarized tunneling using h-BN barriers. These results open the way for integration of 2D monolayer insulating barriers in active spintronic devices and circuits operating at ambient temperature, and for further exploration of their properties and prospects.

show abstract

Voltage-controlled inversion of tunnel magnetoresistance in epitaxial nickel/graphene/MgO/cobalt junctions

Cited by 54 publications

References 36 publications

Protecting nickel with graphene spin-filtering membranes: A single layer is enough

Protecting nickel with graphene spin-filtering membranes: A single layer is enough

Electrical spin injection, transport, and detection in graphene-hexagonal boron nitride van der Waals heterostructures: progress and perspectives

Tunnel magnetoresistance with atomically thin two-dimensional hexagonal boron nitride barriers

Contact Info

Product

Resources

About