相关实验视频
Updated: May 22, 2026
11:41
Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
旋转扭矩切换与坦的巨大的旋转霍尔效应
Luqiao Liu1, Chi-Feng Pai, Y Li
1Cornell University, Ithaca, NY 14853, USA.
Science (New York, N.Y.)
|May 5, 2012
概括
研究人员在β-中发现了一个巨大的旋转霍尔效应 (SHE),使磁铁在室温下能够有效地切换旋转矩. 这一突破推动了用于磁性内存和逻辑应用的自旋电子设备的发展.
科学领域:
- 这就是Spintronics.
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 旋转电流对于旋转电子设备至关重要,但旋转霍尔效应 (SHE) 由于其温和的强度而受到限制.
- 有效地产生自旋电流对于推进磁性存储器和自旋逻辑等技术至关重要.
研究的目的:
- 在β-中报告和描述一个巨大的旋转霍尔效应 (SHE).
- 为了证明这个巨大的SHE在室温下有效切换磁性材料的旋转扭矩的潜力.
- 为实际的自旋电子应用提供一种新的设备设计.
主要方法:
- 用三种独立的实验方法量化β-中巨型旋转霍尔效应 (SHE).
- 对外平面和内平面磁化铁磁体的旋转扭矩切换的演示.
- 制造和测试一个三端装置,集成一个铁磁二层和一个磁道连接点.
主要成果:
- 在β-中观察到一个巨大的旋转霍尔效应 (SHE),产生高效的旋转电流.
- 通过使用产生的旋转电流,可以实现铁磁体的高效室温旋转扭矩切换.
- 一个功能性的三端设备证明了可靠的纳米磁铁切换和读出.
结论:
- 用β-制成的巨型SHE克服了以前的局限性,在室温下实现了高效的旋转扭矩切换.
- 这一发现为开发先进的磁性内存和非挥发性旋转逻辑技术提供了可行的途径.
- 展示的设备设计简单,可靠和高效,有可能加速旋转电子设备的商业化.
相关概念视频
01:13Torque On A Current Loop In A Magnetic Field
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...
01:08Spin–Spin Coupling Constant: Overview
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 have a...
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 have a...
01:17Force On A Current Loop In A Magnetic Field
Magnetic forces on wires carrying current are most frequently applied in motors. A DC motor is a device that converts electrical energy into mechanical work. In motors, wire loops are enclosed in a magnetic field. When current flows through the loops, the magnetic field applies torque, which causes the shaft to rotate. The direction of the current is reversed once the loop's surface area is lined up with the magnetic field, causing a constant torque on the loop. During the process, commutators...
01:23Faraday Disk Dynamo
A Faraday disk dynamo is a DC generator, producing an emf that is constant in time. It consists of a conducting disk that rotates with a constant angular velocity in the magnetic field, perpendicular to the disk's plane. The rotation of the disk causes a change in magnetic flux, which induces an emf, causing opposite charges to develop on the rim and in the center of the disk. The polarity of the induced emf can be determined by the direction of the magnetic field and the direction of the...
01:17Magnetic Damping
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
01:13Magnetic Force Between Two Parallel Currents
Two long, straight, and parallel current-carrying conductors exert a force of equal magnitude on one another. The direction of the force depends on the current direction in the conductors.
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...