Four-wave mixing using polarization grating induced thermal grating in liquids exhibiting circular dichroism

Technical Report · Sat Apr 01 04:00:00 EST 1995

DOI:https://doi.org/10.2172/481612· OSTI ID:481612

Nunes, J A; Tong, W G ^[1]; Chandler, D W; Rahn, L A ^[2]

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1. San Diego State Univ., CA (United States). Dept. of Chemistry
2. Sandia National Lab., Livermore, CA (United States). Combustion Research Facility

A novel four-wave mixing technique for the detection of circular dichroism in optically active liquid samples is demonstrated. When two cross-polarized laser beams are crossed at a small angle in a circular dichroic liquid a weak thermal grating is produced with a phase depending on the sign of the circular dichroism. The authors show that the polarization of one of the beams can be modified to allow coherent interference with an intensity-grating induced thermal grating. A probe beam scattering from the composite grating results in a signal that reveals the sign and magnitude of the circular dichroism. The use of this technique to optimize the signal-to-noise ratio in the presence of scattered light and laser intensity noise is discussed.

• Research Organization: Sandia National Labs., Livermore, CA (United States)
• Sponsoring Organization: USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 481612
• Report Number(s): SAND--95-8221; ON: DE97052383
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
DICHROISM
FREQUENCY MIXING
GRATINGS
LASER RADIATION
LIQUIDS
STRUCTURAL CHEMICAL ANALYSIS