Experiment 7
The Hall Effect: Identifying Carriers
Visualize how the Lorentz force deflects charge carriers to identify their sign and concentration.
Controls
Key Equations
Hall Voltage:
VH = IB / (net)
The sign of VH identifies the carrier type. Carrier concentration n = 1/(|RH|e).
Hall Bar Carrier Animation
VH Reading
-62.42 mV
RH Coeff
6.24e-4
Carrier
n-type
B Direction
Into Page (⊗)
Task: Carrier Deflection
Observe the drift of the electrons (blue). Switch carrier types and notice how the accumulation flips to the opposite face.
Teaching Connection
The Hall effect is one of the few labs that reveals the sign of the charge carrier. Use this to confirm that "holes" behave as real positive particles.
Reflection Questions
- How does increasing the sample thickness (t) affect the measured Hall voltage?
- Explain why the Hall voltage is much larger in semiconductors than in metals.
- What would happen to VH if both the magnetic field B and current I were reversed?