Abstract
The electro-optical Kerr effect induced by a slowly varying electric field in liquid helium at temperatures below the point is investigated. The Kerr constant of liquid helium is measured to be at . Within experimental uncertainty, the Kerr constant is independent of temperature in the range to , which implies that the Kerr constant of the superfluid component of liquid helium is the same as that of normal liquid helium. Pair and higher correlations of He atoms in the liquid phase account for about 23% of the measured Kerr constant. Liquid nitrogen was used to test the experimental setup; the result for the liquid nitrogen Kerr constant is . Kerr effect can be used as a noncontact technique for measuring the magnitude and mapping out the distribution of electric fields inside these cryogenic insulants.
- Received 30 March 2004
DOI:https://doi.org/10.1103/PhysRevLett.93.153003
©2004 American Physical Society