R.Vlokh, O.G.Vlokh, I.Klymiv, D.Adamenko
The paper is devoted to the study of induced gyrotropy (Faraday type and spatial dispersion type) by the magnetic field in crystals with different point groups of symmetry and different optical absorption. According to our experiments Li2B4O7 and SiO2 crystals do not possess magnetogyration because in the first case wavelength of 632.8nm is far from absorption age and in the second one magnetogyration is forbidden in such geometry of experiment. Coefficients of the Faraday effect for Li2B4O7 and SiO2 crystals are a33=1.12*10-10Oe-1 and a33=1.13*10-10Oe-1, respectively. But CdS and (GaxIn1-x)2Se3 (x = 0.3; 0.4) crystals that exhibit strong absorption at l=632.8nm possess a sufficient magnetogyration effect. Determined coefficients of the Faraday effect and magnetogyration for CdS and (GaxIn1-x)2Se3 (x=0.3; 0.4) are a33=5.05*10-9Oe-1, s333=5.7*10-11Oe-1 and a33=9.27*10-9Oe-1, s333=2.45*10-10Oe-1 (x=0.3); a33=9.29*10-9Oe-1, s333=2.43*10-10Oe-1 (x = 0.4) respectively. It is interesting to note that in contrary to the CdS crystals, CdS0.22Se0.78 and CdS0.4Se0.6 nanocrystals embedded in borosilicate glass matrix possess only the Faraday effect (a33=2.06*10-10Oe-1 and a33=2.29*10-10Oe-1, respectively) that is in good agreement with the symmetry conditions and our approach. Our present experiments show that a magnetogyration effect exists in crystals only due to sufficient absorption.
PACS: 78.20.Ls
doi 10.3116/16091833/3/2/166/2002