Single, double and triple superimposed surface relief gratings were sequentially laser-inscribed on azobenzene molecular glass films using a Lloyd’s mirror interferometer. The single gratings had a unidirectional sinusoidal profile, the double gratings had two orthogonal grating vectors, and the triple gratings had three grating vectors separated by 30 degrees. These gratings were coated with silver so that surface plasmons can be generated. The purpose of this study is to understand how photons, which have been converted to a plasmon by a first grating, can be re-emitted again, with a different light polarization, by a second in-plane superimposed grating having a different grating vector orientation.
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