Model No:MREX-BIS
It is noticed that the resistance of the sample changes when the magnetic field is turned on. The phenomenon , called magnetoresistance, is due to thefact that the drift velocity of all the carriers is not same. With the magnetic field on; the Hall voltage V = E t = | v x H | compensates exactly the Lorentz force for carriers with the average velocity; slower carriers will be over compensated and faster one under compensated, resulting in trajectories that are not along the applied field. This results in an effective decrease of the mean free path and hence an increase in resistivity.
It is noticed that the resistance of the sample changes when the magnetic field is turned on. The phenomenon , called magnetoresistance, is due to thefact that the drift velocity of all the carriers is not same. With the magnetic field on; the Hall voltage V = E t = | v x H | compensates exactly the Lorentz force for carriers with the average velocity; slower carriers will be over compensated and faster one under compensated, resulting in trajectories that are not along the applied field. This results in an effective decrease of the mean free path and hence an increase in resistivity.
Setup Consists of the following:
It consists of 4 collinear, equally spaced (2mm), gold plated and individually spring loaded probes mounted on a PCB strip. Two outer probes for supplying the constant current to the sample and two inner probes for measuring the voltage developed across these probes.
Scope of Learning:
Technical Specifications:
Magneto Resistance Meter
Probe
Electromagnet Power supply
Electromagnet
