What is the Hall Effect?
The Hall effect is a phenomenon that occurs in electrically conductive materials and is based on the interaction between an electric current and a magnetic field. It was first discovered by Edwin Hall in 1879.
When does the Hall Effect occur?
The Hall effect occurs when an electric current flows in conductive material and a magnetic field is applied perpendicular to it. As the current moves in one direction, the charge carriers, such as electrons or holes, experience a deflection due to the Lorentz force generated by the interaction between the magnetic field and the moving charge.
The deflection of the charge carriers leads to a charge separation in the material. The negatively charged electrons are deflected towards one side of the material due to the Lorentz force, while the positively charged holes are deflected in the opposite direction. This creates a charge separation across the direction of the current, resulting in an electrical potential difference called the Hall voltage.
The Hall voltage is measured in proportion to the strength of the magnetic field, the current and the reciprocal of the thickness of the material. Thus, the Hall effect enables the determination of the magnetic field strength or the current in a conductive material.
What are applications of the Hall Effect?
An important application of the Hall effect is in Hall sensor technology. Hall sensors consist of a thin strip of conductive material, with a current flowing through it. By applying a magnetic field crosswise to the current flow, the Hall effect produces a measurable Hall voltage that is proportional to the magnetic field strength. This Hall voltage can then be used to detect and measure magnetic fields.