Spin Pumping and Inverse Spin Hall Effect in Germanium

Abstract

We have measured the inverse spin Hall effect (ISHE) in \textit{n}-Ge at room temperature. The spin current in germanium was generated by spin pumping from a CoFeB/MgO magnetic tunnel junction in order to prevent the impedance mismatch issue. A clear electromotive force was measured in Ge at the ferromagnetic resonance of CoFeB. The same study was then carried out on several test samples, in particular we have investigated the influence of the MgO tunnel barrier and sample annealing on the ISHE signal. First, the reference CoFeB/MgO bilayer grown on SiO${}_2$ exhibits a clear electromotive force due to anisotropic magnetoresistance and anomalous Hall effect which is dominated by an asymmetric contribution with respect to the resonance field. We also found that the MgO tunnel barrier is essential to observe ISHE in Ge and that sample annealing systematically lead to an increase of the signal. We propose a theoretical model based on the presence of localized states at the interface between the MgO tunnel barrier and Ge to account for these observations. Finally, all of our results are fully consistent with the observation of ISHE in heavily doped $n$-Ge and we could estimate the spin Hall angle at room temperature to be $\approx$0.001.

34 pages, 14 figures

References in corpus (27)

• Spintronics: Fundamentals and applications
• Spin torque switching with the giant spin Hall effect of tantalum
• Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor
• Enhanced Gilbert Damping in Thin Ferromagnetic Films
• Spin Torque Ferromagnetic Resonance Induced by the Spin Hall Effect
• Direct electronic measurement of the spin Hall effect
• Nonlocal magnetization dynamics in ferromagnetic heterostructures
• Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem
• Electronic measurement and control of spin transport in Silicon
• Detection and quantification of inverse spin Hall effect from spin pumping in permalloy/normal metal bilayers
• Indication of intrinsic spin Hall effect in 4d and 5d transition metals
• Non-collinear Magnetoelectronics
• Observation of the inverse spin Hall effect in silicon
• On the line shape of the electrically detected ferromagnetic resonance
• Evolution of the spin Hall effect in Pt nanowires: Size and temperature effects
• Enhancement of the Spin Accumulation at the Interface Between a Spin-Polarized Tunnel Junction and a Semiconductor
• Spin precession and inverted Hanle effect in a semiconductor near a finite-roughness ferromagnetic interface
• Room-Temperature Electron Spin Transport in a Highly Doped Si Channel
• Comment: "Electrical injection and detection of spin accumulation in silicon at 500 K with magnetic metal / silicon dioxide contacts" [Nature Commun. 2:245 doi:10.1038/ncomms125 (2011)]
• Electrical spin injection and transport in Germanium
• Platinum thickness dependence of the inverse spin-Hall voltage from spin pumping in a hybrid YIG/Pt system
• Crossover from spin accumulation into interface states to spin injection in the germanium conduction band
• Electrical spin injection and accumulation in CoFe/MgO/Ge contacts at room temperature
• Electrical spin injection and detection in Germanium using three terminal geometry
• Electrical injection and detection of spin accumulation in Ge at room temperature
• Dynamical Spin Injection into p-type Germanium at Room Temperature
• Electrical and thermal spin accumulation in germanium

Cited by in corpus (32)

• Spin Pumping and Inverse Spin Hall Effect in Platinum: The Essential Role of Spin-Memory Loss at Metallic Interfaces
• Highly efficient and tuneable spin-to-charge conversion through Rashba coupling at oxide interfaces
• Thermoelectric generation based on spin Seebeck effects
• Electrical Detection of Magnetization Dynamics via Spin Rectification Effects
• Self-induced inverse spin Hall effect in permalloy at room temperature
• Enhanced DC Spin Pumping into a Fluctuating Ferromagnet near Tc
• Experimental evidences of a large extrinsic spin Hall effect in AuW alloy
• An experimental demonstration of room-temperature spin transport in n-type Germanium epilayers
• Gate-tunable spin-charge conversion and a role of spin-orbit interaction in graphene
• Spin-charge interconversion in KTaO${}_3$ two-dimensional electron gases
• Spin pumping into superconductors: A new probe of spin dynamics in a superconducting thin film
• Dirac-Surface-State-Dominated Spin to Charge Current Conversion in the Topological Insulator $(B{i}_{0.22}S{b}_{0.78}{)}_{2}T{e}_3$ Films at Room Temperature
• The valley Nernst effect in WSe${}_2$
• Important role of magnetization precession angle measurement in inverse spin Hall effect induced by spin pumping
• Room-temperature spin transport in n-Ge probed by four-terminal nonlocal measurements
• Charge-spin current conversion in high quality epitaxial Fe/Pt systems: isotropic spin Hall angle along different in-plane crystalline directions
• Metal/SrTiO${}_3$ two-dimensional electron gases for spin-to-charge conversion
• Spin transport and spin conversion in compound semiconductor with non-negligible spin-orbit interaction
• Self-induced inverse spin Hall effect in ferromagnets: demonstration through non-monotonous temperature-dependence in permalloy
• Independence of the inverse spin Hall effect with the magnetic phase in thin NiCu films
• Planar Hall effect induced spin rectification effect and its strong impact on spin pumping measurements
• Inverse Edelstein effect of the surface states of a topological insulator
• Negligible thermal contributions to the spin pumping signal in ferromagnetic metal-Platinum bilayers
• Spin-wave-induced lateral temperature gradient in a YIG thin film/GGG system excited in an ESR cavity
• Efficient spin-to-charge interconversion in Weyl semimetal TaP at room temperature
• Unified formulation of interfacial magnonic pumping from non-collinear magnets
• Direct imaging of the ac component of the pumped spin polarization with element specificity
• Unraveling the Spin-to-Charge Current Conversion Mechanism and Charge Transfer Dynamics at Interface of Graphene/WS${}_2$ Heterostructures at Room Temperature
• Interfacial spin-orbit-coupling-induced strong spin-to-charge conversion at an all-oxide ferromagnetic /quasi-two-dimensional electron gas interface
• Spin pumping into a spin glass material
• Self-induced spin pumping and inverse spin Hall effect in single FePt thin films
• RF field characterization and rectification effects in spin pumping and spin-torque FMR for spin-orbitronics