Open AccessModulation of the azimuth of polarization of reconstruction beam on the diffraction efficiency of anisotropic gratings recorded in bacteriorhodopsin films by two parallel linearly polarized beams
Author(s) -
Gao Peng,
Baoli Yao,
Jianhua Han,
Liju Chen,
Yingli Wang,
Ming Lei
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.2952
Subject(s) - optics , diffraction efficiency , diffraction , azimuth , polarization (electrochemistry) , linear polarization , grating , materials science , perpendicular , physics , diffraction grating , beam (structure) , radial polarization , anisotropy , laser beam quality , laser , laser beams , chemistry , geometry , mathematics
When the linearly polarized object and reference beams with the same polarization direction are used for recording gratings in bacteriorhodopsin films, the azimuth of polarization of the reconstruction beam has an influence on the diffraction efficiency. By using Jones matrices to analyze this phenomenon, we find that the azimuth of polarization of the reconstruction beam makes a cosine modulation on the diffraction efficiency. The diffracted beam is linearly polarized only when the polarization of the reconstruction beam is parallel or perpendicular to that of the recording beams; otherwise, the diffracted beam becomes elliptically polarized. The azimuth of polarization of the reconstruction beam produces a positive cosine modulation on the peak diffraction efficiency, but a negative cosine modulation on the steady diffraction efficiency (with phase difference π). By adding auxiliary violet light during grating formation, the saturation of the grating can be restrained; as a result, the negative cosine modulation of the steady diffraction efficiency changes to the positive cosine modulation and also the steady diffraction efficiency is increased apparently.