Nontrivial magnetic field related phenomena in the single-layer graphene on ferroelectric substrate

Abstract

The review is focused on our recent predictions of nontrivial physical phenomena taking place in the nanostructure single-layer grapheme on ferroelectric substrate, which are related with magnetic field. In particular we predicted that 180-degree domain walls in a strained ferroelectric film can induce p-n junctions in a graphene channel and lead to the unusual temperature and gate voltage dependences of the perpendicular modes ν of the integer quantum Hall effect. The non-integer numbers and their irregular sequence principally differ from the conventional sequence ν= 3/2, 5/3. The unusual v-numbers originate from significantly different numbers of the edge modes, ν1 and ν2, corresponding to different concentration of carriers in the left (n1) and right (n2) ferroelectric domains of p-n junction boundary. The difference between n1 and n2 disappears with the vanishing of the film spontaneous polarization in a paraelectric phase, which can be varied in a wide temperature range by an appropriate choice of misfit strain originated from the film-substrate lattice mismatch. Next we studied the electric conductivity of the system ferromagnetic dielectric - graphene channel - ferroelectric substrate. The magnetic dielectric locally transforms the band spectrum of graphene by inducing an energy gap in it and making it spin-asymmetric with respect to the free electrons. It was demonstrated, that if the Fermi level in the graphene channel belongs to energy intervals, where the graphene band spectrum, modified by EuO, becomes sharply spin-asymmetric, such a device can be an ideal non-volatile spin filter. The practical application of the system under consideration would be restricted by a Curie temperature of a ferromagnet. Controlling of the Fermi level (e.g. by temperature that changes ferroelectric polarization) can convert a spin filter to a spin valve.

20 pages, 5 figures. arXiv admin note: text overlap with arXiv:1901.04550

References in corpus (11)

• Electric Field Effect in Atomically Thin Carbon Films
• Unconventional Integer Quantum Hall effect in graphene
• Effect of epitaxial strain on the spontaneous polarization of thin film ferroelectrics
• Magnetic Insulator-Induced Proximity Effects in Graphene: Spin Filtering and Exchange Splitting Gaps
• Quantized Transport in Graphene p-n Junctions in Magnetic Field
• Electronic spin drift in graphene field effect transistors
• MagnetoResistance of graphene-based spin valves
• Spin filter and spin valve in ferromagnetic graphene
• Limits for the graphene on ferroelectric domain wall p-n-junction rectifier for different regimes of current
• Electric-field-induced extremely large change in resistance in graphene ferromagnets
• Magnetic dielectric- graphene- ferroelectric system as a promising non-volatile device for modern spintronics