We report on the investigation and characterization of an optically tunable filtering effect, observed in a waveguide grating made of alternated strips of photocurable polymer and a mixture of azo-dye-doped liquid crystal. The grating is sandwiched between two borosilicate glasses, one of which includes an ion-exchanged channel waveguide, which confines the optical signal to be filtered. Exposure to a low power visible light beam modifies the azo-dye molecular configuration, thus allowing the filtered wavelength to be tuned over a 6.6 nm range. Simulations of the filtering response are well described with our experimental findings. © 2011 Optical Society of America.
Observation of tunable optical filtering in photosensitive composite structures containing liquid crystals / Giovanni, Gilardi; DE SIO, Luciano; Romeo, Beccherelli; Asquini, Rita; D'Alessandro, Antonio; Cesare, Umeton. - In: OPTICS LETTERS. - ISSN 0146-9592. - STAMPA. - 36:24(2011), pp. 4755-4757. [10.1364/ol.36.004755]
Observation of tunable optical filtering in photosensitive composite structures containing liquid crystals
DE SIO, LUCIANO;ASQUINI, Rita;D'ALESSANDRO, Antonio;
2011
Abstract
We report on the investigation and characterization of an optically tunable filtering effect, observed in a waveguide grating made of alternated strips of photocurable polymer and a mixture of azo-dye-doped liquid crystal. The grating is sandwiched between two borosilicate glasses, one of which includes an ion-exchanged channel waveguide, which confines the optical signal to be filtered. Exposure to a low power visible light beam modifies the azo-dye molecular configuration, thus allowing the filtered wavelength to be tuned over a 6.6 nm range. Simulations of the filtering response are well described with our experimental findings. © 2011 Optical Society of America.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.