Name: hall voltage and charge carriers
Uploaded: 2025-05-22T09:05:51.000Z
Duration: 1 min 30 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

motion-and-stability-forces-and-interactions

Motion and Stability- Forces and Interactions

PS.PSc.6.4

The Hall Effect

전하 운반체로 전자를 사용하는 직사각형 전류 운반 도체를 생각해 보십시오. 자기장이 도체의 평면에 수직으로 가해지면 편향 자기력으로 인해 직선으로 움직이는 전자가 표류합니다.
전자는 도체의 한쪽에 축적되어 다른 쪽에 과도한 양전하를 남깁니다. 이 전하 분리는 도체 내에 전기장을 생성하여 자기력에 반대하는 각 전자에 전기력을 가합니다.
평형 상태에서 전기력의 크기는 자기력의 균형을 유지하여 전자의 더 이상의 이동을 중지합니다. 도체의 양쪽 사이의 전위차는 홀 전압입니다.
드리프트 속도를 전류로 표현함으로써 홀 전압은 전하 캐리어의 수 밀도를 측정하는 데에도 사용할 수 있습니다.
홀 프로브는 홀 전압과 도체의 알려진 매개변수에서 알 수 없는 자기장의 크기를 측정합니다.
이 발견의 중요한 응용 분야는 홀 전압의 극성이 도체의 전하 캐리어가 음수인지 양수인지를 암시한다는 것입니다.

<ol>
	<li>오픈스택스. (2019). 대학 물리학 Vol. 2. [웹 버전]. 514-516 <a href="https://openstax.org/books/university-physics-volume-2/pages/11-6-the-hall-effect"에서 검색 함>https://openstax.org/books/university-physics-volume-2/pages/11-6-the-hall-effect</a></li>
</ol>

홀 효과

1879년 Edwin H. Hall은 전도성 물질에서 주요 전하 캐리어의 극성을 식별하는 데 사용할 수 있는 실험을 고안했습니답안 역사적인 관점에서 볼 때, 이 실험은 대부분의 금속에 있는 전하 캐리어가 음수임을 입증한 최초의 실험이었습니답안

<img alt="Figure1" src="/files/ftp_upload/13772/13772_Figure_1.png" style="text-align: center" />

일정한 자기장에서 너비가 L인 금속판을 생각해 보세요. 전자는 오른쪽에서 왼쪽으로 이동하므로 전자가 받는 자기력은 전자를 슬래브의 상단 가장자리로 밀어냅니답안 이로 인해 슬래브 상단 가장자리에 과도한 음전하가 남고 슬래브 하단 가장자리에 과도한 양전하가 남게 되어 전기장이 바닥에서 상단으로 향하게 됩니답안 양쪽 가장자리의 전하 농도는 평형 조건이 확립될 때까지 축적됩니답안 평형 상태에서는 전자에 작용하는 한 방향의 전기력이 반대 방향의 자기력과 균형을 이룹니답안 전기장과 자기장이 서로 수직인 이러한 시나리오를 교차장 상황이라고 합니답안

슬래브 I의 전류는 표류 속도 vd와 단면적 슬래브, A. 홀 전압이라고도 하는 스트립 가장자리 사이의 전위차는 다음과 같이 제공됩니답안

<img alt="Equation1" src="/files/ftp_upload/13772/13772_Equation_1.png" style="text-align: center; height: 40px;" />

홀 전압의 극성은 전하 캐리어가 양극인지 음극인지를 나타냅니답안 이 효과의 또 다른 중요한 적용은 알려진 전하 캐리어 밀도를 가진 재료에 대한 것입니답안 측정된 홀 전압은 알려지지 않은 자기장의 값을 제공할 수 있습니답안 정밀한 측정에 사용되는 전자석의 자기장이 매우 안정적이어야 하는 연구실에서는 '홀 프로브'가 사용됩니답안 일반적으로 현장을 조절하기 위해 전자 회로의 일부로 사용됩니답안

Edwin H. Hall은 1879 년에 전도성에서 우세한 전하 캐리어의 극성을 식별하는 데 사용할 수있는 실험을 고안했습니다.

Education

교육

JoVE Core

Physics

물리학

Unit 1

제1단원

Magnetic Forces and Fields

자기력과 자기장

KEY TERMS AND CONCEPTS

주요 용어 및 개념

hall voltage and charge carriers

Hall voltage and charge carriers are explained through Edwin H. Hall’s 1879 experiment. His setup helped identify the polarity of the main charge carriers in a conducting material. It also showed, for the first time, that the charge carriers in most metals are negative.

A metal slab is placed in a constant magnetic field. The electrons move from right to left, so the magnetic force pushes them toward the top edge of the slab. This leaves excess negative charge at the top and excess positive charge at the bottom. As a result, an electric field forms from the bottom edge to the top edge.

The charge buildup continues until equilibrium is reached. At that point, the electric force on the electrons balances the magnetic force in the opposite direction. This is called a crossed-field situation because the electric and magnetic fields are perpendicular to each other. The current in the slab, I, can be written in terms of the drift velocity, v d, and the cross-sectional area, A.

The potential difference between the two edges is called the Hall voltage. Its polarity reveals whether the charge carriers are positive or negative. When the density of charge carriers is known, the Hall voltage can also be used to find an unknown magnetic field. In research labs, a Hall probe is often used in electronic circuits to help regulate electromagnet fields so they stay steady for precise measurements.

Hall Voltage and Charge Carriers

magnetism

Magnetic Poles and Everyday Uses

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motion-of-a-charged-particle-in-a-magnetic-field

Charged Particle Paths in Magnetic Fields

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magnetic force

Magnetic Fields and Moving Charges

Magnetic fields and moving charges create magnetic force. A moving electric charge, or a current made of many moving charges, produces a magnetic field. When another current or moving charge enters that field, it feels a magnetic force in response. At the atomic level, magnetic forces come from interactions between moving electrons in the atoms of two bodies. The strength of magnetic force depends on several factors. It increases with the size of the charge and with the strength of the...

magnetic force on a current-carrying conductor

magnetic-force-on-a-current-carrying-conductor

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magnetic force on current-carrying wires: example

magnetic-force-on-current-carrying-wires-example

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torque on a current loop in a magnetic field

torque-on-a-current-loop-in-a-magnetic-field

Current Loop Torque in Electric Motors

Current loop torque in electric motors shows how magnetic force can make a wire loop rotate. In an electric motor, loops of wire sit between magnets in a magnetic field. When current flows through the loops, the field applies torque. This rotation turns a shaft and converts electrical energy into mechanical energy. A rectangular current-carrying loop with N turns in a uniform magnetic field has zero net force. Even so, it can still experience net torque. The torque depends on the current I,...

the hall effect

Hall voltage and charge carriers are explained through Edwin H. Hall’s 1879 experiment. His setup helped identify the polarity of the main charge carriers in a conducting material. It also showed, for the first time, that the charge carriers in most metals are negative. A metal slab is placed in a constant magnetic field. The electrons move from right to left, so the magnetic force pushes them toward the top edge of the slab. This leaves excess negative charge at the top and excess positive...

thomson's e/m experiment

Electron Speed Selector in Thomson’s Tube

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key terms and concepts

Learn how Hall voltage forms in a magnetic field, how it reveals charge carrier polarity, and how Hall probes help measure and control magnetic fields.

Hall Voltage and Charge Carriers | JoVE K12

physics

JoVE Core Physics introduces the theory and application of fundamental physics topics, including kinematics, dynamics, fluid mechanics, statics, waves, and acoustics, with concise and easy-to-understand animated videos. Additionally, the scientist-in-action videos demonstrate the application of related concepts in classical and original research experiments performed in today's laboratories worldwide.

Virginia  Standards of Learning

HIgh School

PS.9

PS.9.d

Alabama Course of Study Science

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Hall Voltage and Charge Carriers

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