MEASUREMENT OF KERR CONSTANTS OF CONDUCTING LIQUIDS

An apparatus is described to measure the Kerr constant of conducting as well as non-conducting liquids and solutions. High-voltage pulses of short duration (1 · 5 µs) are applied across the Kerr cell and the resultant birefringence is measured by a novel signal-nulling technique. New expressions are derived for the null conditions for an optically active birefringent medium. Results are presented at 633 nm and 293 K for water, methanol, ethanol, propan-1-ol and propan-2-ol. The Kerr constant of water (3.0 × 10-14m V-2) was in good agreement with recent determinations. © 1979, CSIRO. All rights reserved.