The
resistivity and Hall voltage of a rectangular Ge and GaAs sample are measured
as a function of temperature and magnetic field. The band spacing, the specific
conductivity, the type of charge carrier and the mobility of the charge
carriers are determined from the measurements.

Ge n-type : b=13mm,
c=28mm, d=5X10^-4m, n=10²²/m³

Ge(p-type)
: b=13mm, c=28mm, d=5X10^-4m, n=10²²/m³

GaAs(n-type) : b=13mm, c=28mm, d=5X10^-4m,
n=10²²/m³

Main
: Temp display, Adjusting current and direction

Core
and Coils : 400mT(max), 600turns

Tesla
meter : +/- 1000mT, offset