Strong modulation of spin currents in bilayer graphene by static and fluctuating proximity exchange fields

Abstract

Two dimensional (2D) materials provide a unique platform to explore the full potential of magnetic proximity driven phenomena, which can be further used for applications in next generation spintronic devices. Of particular interest is to understand and control spin currents in graphene by the magnetic exchange field of a nearby ferromagnetic material in graphene/ferromagnetic-insulator (FMI) heterostructures. Here, we present the experimental study showing the strong modulation of spin currents in graphene layers by controlling the direction of the exchange field due to FMI magnetization. Owing to clean interfaces, a strong magnetic exchange coupling leads to the experimental observation of complete spin modulation at low externally applied magnetic fields in short graphene channels. Additionally, we discover that the graphene spin current can be fully dephased by randomly fluctuating exchange fields. This is manifested as an unusually strong temperature dependence of the non-local spin signals in graphene, which is due to spin relaxation by thermally-induced transverse fluctuations of the FMI magnetization.

References in corpus (33)

• The Raman Fingerprint of Graphene
• Boron nitride substrates for high-quality graphene electronics
• Spin torque switching with the giant spin Hall effect of tantalum
• Electronic spin transport and spin precession in single graphene layers at room temperature
• Hofstadter's butterfly in moire superlattices: A fractal quantum Hall effect
• Gate-induced insulating state in bilayer graphene devices
• Graphene Spintronics
• Semiconductor Spintronics
• Theory of magnon-driven spin Seebeck effect
• Theory of the Spin Seebeck Effect
• Proximity-induced ferromagnetism in graphene revealed by anomalous Hall effect
• Scaling of spin Hall angle in 3d, 4d and 5d metals from Y3Fe5O12/metal spin pumping
• Tunneling Spin Injection into Single Layer Graphene
• Tunneling Spin Injection into Single Layer Graphene (Supplementary Information)
• Spin Relaxation in Single Layer and Bilayer Graphene
• Strong interfacial exchange field in the graphene/EuS heterostructure
• Probing the Electronic Structure of Bilayer Graphene by Raman Scattering
• Magnetic Moment Formation in Graphene Detected by Scattering of Pure Spin Currents
• Linear-response theory of spin Seebeck effect in ferromagnetic insulators
• Observation of Long Spin Relaxation Times in Bilayer Graphene at Room Temperature
• Controlling spin relaxation in hexagonal BN-encapsulated graphene with a transverse electric field
• Proximity induced room-temperature ferromagnetism in graphene probed with spin currents
• Spin Transport and Relaxation in Graphene
• Electrical Detection of Spin Precession in Single Layer Graphene Spin Valves with Transparent Contacts
• Large Spin Pumping from Epitaxial Y3Fe5O12 Thin Films to Pt and W Layers
• Determination of the spin-lifetime anisotropy in graphene using oblique spin precession
• Electrical spin injection into graphene through monolayer hexagonal boron nitride
• Nanosecond spin relaxation times in single layer graphene spin valves with hexagonal boron nitride tunnel barriers
• Electric-Field-control of spin rotation in bilayer graphene
• Electronic Spin Transport in Dual-Gated Bilayer Graphene
• Modulation of pure spin currents with a ferromagnetic insulator
• Control of spin current by a magnetic YIG substrate in NiFe/Al nonlocal spin valves
• Absence of hyperfine effects in ${}^{13}$C-graphene spin valve devices

Cited by in corpus (36)

• Room Temperature Intrinsic Ferromagnetism in Epitaxial Manganese Selenide Films in the Monolayer Limit
• Van der Waals heterostructures for spintronics and opto-spintronics
• Opto-Valleytronic Spin Injection in Monolayer MoS2/Few-Layer Graphene Hybrid Spin Valves
• Van der Waals spin valves
• Tailoring magnetic insulator proximity effects in graphene: First-principles calculations
• Electrical and Thermal Generation of Spin Currents by Magnetic Graphene
• Bias induced up to 100% spin-injection and detection polarizations in ferromagnet/bilayer-hBN/graphene/hBN heterostructures
• Magnetic proximity in a van der Waals heterostructure of magnetic insulator and graphene
• Spin Hall effect and Weak Antilocalization in Graphene/Transition Metal Dichalcogenide Heterostructures
• Spin Proximity Effects in Graphene/Topological Insulator Heterostructures
• Spin inversion in graphene spin valves by gate-tunable magnetic proximity effect at one-dimensional contacts
• Electrical spin injection, transport, and detection in graphene-hexagonal boron nitride van der Waals heterostructures: progress and perspectives
• Strong and Tunable Spin Lifetime Anisotropy in Dual-Gated Bilayer Graphene
• Electrically tunable exchange splitting in bilayer graphene on monolayer Cr${}_2$X${}_2$Te${}_6$ with X=Ge, Si, and Sn
• Magnetic Proximity Effect in Pt/CoFe2O4 Bilayers
• Twist- and gate-tunable proximity spin-orbit coupling, spin relaxation anisotropy, and charge-to-spin conversion in heterostructures of graphene and transition-metal dichalcogenides
• Anisotropic Magnetoresistance and Nontrivial Spin Hall Magnetoresistance in Pt/$\alpha$-Fe${}_2$O${}_3$ Bilayers
• Synthetic antiferromagnetic coupling between ultra-thin insulating garnets
• Electrically inert h-BN/bilayer graphene interface in all-2D-heterostructure FETs
• Engineering Proximity Exchange by Twisting: Reversal of Ferromagnetic and Emergence of Antiferromagnetic Dirac Bands in Graphene/Cr${}_2$Ge${}_2$Te${}_6$
• Effective Interactions in a Graphene Layer Induced by the Proximity to a Ferromagnet
• Spontaneous Valley Spirals in Magnetically Encapsulated Twisted Bilayer Graphene
• Towards fully two-dimensional spintronic devices
• Unveiling multiferroic proximity effect in graphene
• Magnetic proximity effect at the interface of two-dimensional materials and magnetic oxide insulators
• Probing Tunneling Spin Injection into Graphene via Bias Dependence
• Long-range p-d exchange interaction in a ferromagnet-semiconductor Co/CdMgTe/CdTe quantum well hybrid structure
• Modeling the Oblique Spin Precession in Lateral Spin Valves for Accurate Determination of Spin Lifetime Anisotropy: Effect of Finite Contact Resistance and Channel Length
• Detection of the interfacial exchange field at a ferromagnetic insulator-nonmagnetic metal interface with pure spin currents
• Spin absorption by in situ deposited nanoscale magnets on graphene spin valves
• Tunable moire spinons in magnetically encapsulated twisted van der Waals quantum spin-liquids
• Bias dependent spin injection into graphene on YIG through bilayer hBN tunnel barriers
• Universal Current Correlations Induced by the Majorana and Fermionic Andreev Bound States
• Spin-dependent edge states in two-dimensional Dirac materials with a flat band
• Giant Spin Transport Anisotropy in Magnetic Topological Insulators
• Valley-Polarized Quantum Anomalous Hall Phase in Bilayer Graphene with Layer-Dependent Proximity Effects