Halljännitteeseen

Halljännitteeseen, a Finnish term, translates to "Hall voltage" in English. It refers to the potential difference that is generated across an electrical conductor when it is exposed to a magnetic field perpendicular to the direction of the electric current flowing through it. This phenomenon is a direct consequence of the Lorentz force acting on the moving charge carriers within the conductor.

When a current flows through a conductor, such as a metal or a semiconductor, it consists of charged particles (usually electrons) moving in a specific direction. If a magnetic field is applied perpendicular to this direction of motion, each moving charge carrier experiences a force, known as the Lorentz force, which is directed perpendicular to both the velocity of the charge carrier and the magnetic field. This force causes the charge carriers to deflect towards one side of the conductor.

As charge carriers accumulate on one side and are depleted from the other, an electric field builds up across the conductor. This electric field creates a potential difference, the Hall voltage, which opposes the further deflection of charge carriers by the Lorentz force. Eventually, a steady state is reached where the electric force due to the Hall voltage exactly balances the magnetic Lorentz force. The magnitude of the Hall voltage depends on the strength of the magnetic field, the current flowing through the conductor, the geometry of the conductor, and a property of the material called the Hall coefficient, which is related to the charge carrier density and type. The Hall effect has various practical applications, including magnetic field sensors and measurements of material properties.