Related Experiment Video
Updated: Mar 26, 2026
11:41
Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
24.0K
Spin-orbit torque in Pt/CoNiCo/Pt symmetric devices.
Meiyin Yang1, Kaiming Cai1, Hailang Ju2
1SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China.
Scientific Reports
|February 10, 2016
Summary
This study shows that damping-like torques from the spin Hall effect dominate magnetization switching in Pt/FM/Pt devices, with negligible field-like torques. Results align with micromagnetic simulations, clarifying spin-orbit torque contributions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Current-induced magnetization switching is key for energy-efficient data storage.
- The roles of damping-like and field-like torques in spin-orbit torque devices are debated.
- Heavy metal/ferromagnet (FM) multilayers are promising for spintronic applications.
Purpose of the Study:
- To investigate the contributions of damping-like and field-like torques in a symmetric Pt/FM/Pt device.
- To quantitatively analyze spin-orbit effective fields and their relation to magnetization switching.
- To understand the influence of in-plane magnetic fields on magnetization switching dynamics.
Main Methods:
- Fabrication and characterization of a symmetric Pt/FM/Pt device.
- Electrical current-induced magnetization switching experiments.
- Quantitative analysis of spin-orbit effective fields.
- Micromagnetic simulations to model switching behavior.
Main Results:
- Demonstrated strong damping-like torque originating from the spin Hall effect.
- Observed unmeasurable field-like torque, likely due to the Rashba effect.
- Quantitative spin-orbit effective fields were consistent with switching fields after thermal fluctuation correction.
- Revealed a non-linear dependence of magnetization switching on in-plane magnetic field.
Conclusions:
- The spin Hall effect is the dominant source of torque for magnetization switching in this Pt/FM/Pt system.
- Rashba-effect-induced field-like torques are negligible in this symmetric structure.
- Micromagnetic simulations accurately explain the observed switching dynamics and field dependencies.
Related Concept Videos
01:08Spin–Spin Coupling Constant: Overview
1.6K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.6K
01:13Angle of Twist: Problem Solving
862
An electric motor applies a torque of 700 N·m to an aluminum shaft, triggering a stable rotation. Two pulleys, B and C, are subjected to torques of 300 N·m and 400 N·m, respectively. The modulus of rigidity is provided as 25 GPa. With the knowledge of the length and diameter of each segment, the twist angle between the two pulleys can be computed. First, a section cut is made between pulleys B and C, and the cut cross-section is analyzed using a free-body diagram. Given that the torque...
862
01:13Torque On A Current Loop In A Magnetic Field
6.4K
The most common application of magnetic force on current-carrying wires is in electric motors. These consist of loops of wire, which are placed between the magnets with a magnetic field. When current flows through the loops, the magnetic field applies torque, which causes the shaft to rotate, thus converting electrical energy to mechanical energy.
Consider a rectangular current-carrying loop containing N turns of wire, placed in a uniform magnetic field. The net force on a current-carrying loop...
Consider a rectangular current-carrying loop containing N turns of wire, placed in a uniform magnetic field. The net force on a current-carrying loop...
6.4K
01:10Torque
23.3K
Torque is an important quantity for describing the dynamics of a rotating rigid body. We see the application of torque in many ways in the world, such as when pressing the accelerator in a car, which causes the engine to apply additional torque on the drivetrain. Here, we define torque and provide a framework to create an equation to calculate torque for a rigid body with fixed-axis rotation.
Torque can be considered as the rotational counterpart to force. Since forces change the translational...
Torque can be considered as the rotational counterpart to force. Since forces change the translational...
23.3K
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
1.9K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.9K
01:15Torque Free Motion
903
The torque-free motion refers to the movement of a rigid body in space when no external torques are acting upon it. This type of motion can be observed in environments where there are no external forces or frictions, like in outer space. For example, a rotation of Mars in space is a torque-free motion. Mars is an axisymmetric object, meaning it has an axis of symmetry along which it rotates, designated as the z-axis. The rotating frame of reference is defined such that the center of mass of...
903