Abstract :
The paper describes experiments on the measurement of microwave power at 10 Gc/s employing the Hall effect produced in single crystals of n- and p-type germanium when erected on the axis of a hollow metal rectangular waveguide carrying the power. So far as is known, this is the first recorded observation of the Hall effect at this frequency, and it has been shown possible to apply the effect, with the help of a suitable phase-adjustment device, to the design of a wattmeter. For this purpose the Hall output from a crystal was calibrated against the power measured independently, and the relationship was found to be practically linear. From these power measurements and consideration of the conditions of operation of the crystal, the Hall coefficients for the n- and p-types of germanium used were deduced and shown to be of the same order of magnitude as the d.c. values. An investigation of the impedance of the crystal circuit led to the conclusion that the contribution to the Hall effect from the displacement current in the crystal was very small compared with that of the conduction current. The success of this application depends largely upon the development of suitable crystal units, and towards that end new techniques were introduced.
