Optical Kerr effect in biopolymer solutions

✍ Scribed by H. J. Coles; B. R. Jennings

• Publisher: Wiley (John Wiley & Sons)
• Year: 1975
• Tongue: English
• Weight: 520 KB
• Volume: 14
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1975.360141212

✦ Synopsis

Abstract

The electric field in a single mode, YAG laser beam has been used to induce orientational birefringence in solutions of tobacco rattle virus, DNA, heparin, and hyaluronic acid. Using this laser in its “fixed‐Q” mode, laser pulses were generated which persisted for up to 200 μsec in which the effective electric field vector rose to 5 kV cm^−1^. The birefringence amplitudes so produced had a quadratic dependence on the effective field strength and thus obeyed Kerr's law. From the birefringence decay rates, relaxation times were determined which, by comparison with the birefringence induced by pulsed static electric fields revealed the biopolymer orientational origins of the effects. This indicated how these experiments can lead to the evaluation of particle geometry, the electronic contribution to electrical polarizabilities, and the optical polarizability of biopolymers in solution.