Photo-Hall Measurement by an Improved Redfield Method

Abstract

Improvements in electrodes and in instrumentation allow measurement of Hall mobilities as low as 1 cm²/V·sec in photoconducting insulators. Resistance strip electrodes are replaced by parallel wire electrostatic potential dividers. Pulsed photocurrents resulting from electric fields of alternating polarity are averaged in a dual channel ``boxcar.'' This signal is then averaged over multiple field sweeps of alternating polarity by a small digital computer.