Experimental evidence of the B 2 and B 3 dependent circular birefringence of chiral molecules in high magnetic fields

Abstract

The rotation of the plane of polarization of light passing through chiral media in the Faraday geometry of a magnetic field B and light propagation vector k have been measured in high magnetic fields of induction up to 30 T and a laser beam wavelength λ = 488 nm. The optically active enantiomers of neat α-methylbenzylamine and solutions in water of tartaric, malic and lactic acids, leucine and threonine exhibit dependence of the induced rotation of the light polarization plane on B 2 and B 3. The effect is reported of the magnetic field B 2 induced circular birefringence of laevorotatory and dextrorotatory enantiomers. Also differences are found in the effective rotation of the plane of polarization in the parallel (α↑↑) and antiparallel (α↑↓) configurations of B and k acting on a chiral medium. The first quantitative determination is made of the nonlinear (B 3) Faraday effect in chiral media. The linear in B circular birefringence makes the largest contribution to the B 2 and B 3 dependent rotation.