Probing magnetism in 2D van der Waals crystalline insulators via electron tunneling

By Dahlia R. Klein, David MacNeill, J. Lado, D. Soriano, E. Navarro-Moratalla, Kenji Watanabe, Takashi Taniguchi, S. Manni, Paul C. Canfield, J. Fern'andez-Rossier and 1 more. Science, 2018

864 citations recorded by the source corpus.

An intrinsic magnetic tunnel junction An electrical current running through two stacked magnetic layers is larger if their magnetizations point in the same direction than if they point in opposite directions. These so-called magnetic tunnel junctions, used in electronics, must be carefully engineered. Two groups now show that high magnetoresistance intrinsically occurs in samples of the layered material CrI3 sandwiched between graphite contacts. By varying the number of layers in the samples, Klein et al. and Song et al. found that the electrical current running perpendicular to the layers was largest in high magnetic fields and smallest near zero field. This observation is consistent with adjacent layers naturally having opposite magnetizations, which align parallel to each other in high magnetic fields. Science, this issue p. 1218, p. 1214 The atomic layers of the material CrI3 act as spin filters in graphite/CrI3/graphite junctions. Magnetic insulators are a key resource for next-generation spintronic and topological devices. The family of layered metal halides promises varied magnetic states, including ultrathin insulating multiferroics, spin liquids, and ferromagnets, but device-oriented characterization methods are needed to unlock their potential. Here, we report tunneling through the layered magnetic insulator CrI3 as a function of temperature and applied magnetic field. We electrically detect the magnetic ground state and interlayer coupling and observe a field-induced metamagnetic transition. The metamagnetic transition results in magnetoresistances of 95, 300, and 550% for bilayer, trilayer, and tetralayer CrI3 barriers, respectively. We further measure inelastic tunneling spectra for our junctions, unveiling a rich spectrum consistent with collective magnetic excitations (magnons) in CrI3.

Subfields: Electrical and Electronic Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/13affa0aeb825cb25d46d064755d358dc1bf4464

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Electrical and Electronic Engineering

In Materials Chemistry

Citations in the corpus

Probing and controlling magnetic states in 2D layered magnetic materials (2019, neutral): “In addition to in-plane transport measurements, out-of-plane magnetic tunnel junctions in which 2D magnetic materials serve as the electrodes have also been demonstrated 115–117 (fig.”
Magnon Transport in Quasi-Two-Dimensional van der Waals Antiferromagnets (2019, background): “For example, giant tunneling magnetoresistance in bilayer CrI3 has been demonstrated [17-19], which is much higher compared to conventional single-crystalline-MgO barrier based ferromagnetic tunneling junctions [20,21].”
Colloquium : Spintronics in graphene and other two-dimensional materials (2019, background): “Kochan, Denis, Susanne Irmer, Martin Gmitra, and Jaroslav Fabian (2015), “Resonant Scattering by Magnetic Impurities as a Model for Spin Relaxation in Bilayer Graphene,” Phys.”
Two-dimensional magnetic crystals and emergent heterostructure devices (2019, methodology): “(C and D) MTJ based on graphite-CrI3-graphite (126).”