Hall Effect in N- and P-type Germanium at 24 Gc

A method to measure Hall mobility at microwave frequencies using a double mode cavity is presented. Hall mobility measured this method corresponds to \(μH{=}(1/B){·}|σ₁|/(σ₀)\), where σ 0 and σ 1 are a diagonal and an off-diagonal components of conductivity matrix, and it is expected to be frequency independent if a constant relaxation time is assumed. Frequency dependence is expected when the energy dependent relaxation time is assumed. For n -type germanium, Hall mobility measured this method at 24 Gc is in excellent agreement with that predicted from the theory using d.c. value and assuming acoustical mode scattering, between room temperature and 100°K. For p -type germanium, the same consideration explains the essential part of the difference between experimental values at 24 Gc and d.c., though there remains some discrepancies to be clarified.