Spectral, Morphological and Dynamical Analysis of a Holographic Grating Recorded in a Photo-Mobile Composite Polymer Mixture

Abstract

We report on the morphological, spectral and dynamical characterization of one-dimensional transmission holographic volume phase gratings, whose refractive index contrast and nanometric pitch are dynamically controlled by an incident laser light. The grating is obtained by the photo-polymerization of a recently developed photo-mobile holographic composite polymer material. The observed changes in the refractive index contrast and grating pitch strongly suggest that the reversible all-optical real-time modulation of the obtained diffraction efficiency is induced by nano-fluidics.

Light-Controlled Direction of Distributed Feedback Laser Emission by Photo-Mobile Polymer Films

“…This fraction of light is partially absorbed and induces a symmetric flow of the photo-phobic part of the mixture towards the center of the cell, making impossible the formation of the polymer walls of the grating. On the contrary, we succeeded in writing high resolution transmission gratings, directly in PMP films [ 50 , 52 , 53 , 77 ]. Our approach overcomes these limits, by introducing a recently developed mixture suitable for DFB-laser fabrication [ 46 ].…”

“…Acting this way, at the same time we have the formation of the PMP-film and its link to the grating border. The PMP-film containing the grating is now ready to be peeled-off from the glass substrate and bent in a free standing configuration by using an external low-power light source [ 50 , 51 , 52 , 53 , 79 ] (see Figure S2 in the Supporting Information ). At this stage the PMP-DFB film can be irradiated by an external pulsed laser that induces lasing at the edge of the photonic band-gap [ 46 ].…”

“…Recently, a novel class of polymers (photo-mobile polymers, PMPs) in which a mechanical motion can be induced and controlled by an external light [ 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 ] is emerging.…”

“…Many papers also report about gratings recorded on PMP-films as surface relief gratings [ 72 , 73 , 74 , 75 , 76 ]. Our group has recently reported on the recording of holographic volume transmission gratings in PMP-films [ 50 , 53 , 77 ]. However, as far as we know, the recording of an efficient reflection grating in a PMP film is still not realized.…”

Light-Controlled Rotational Speed of an Acoustically Levitating Photomobile Polymer Film

“…Composite polymer materials, already used in a wide variety of applications such as [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ], play a fundamental role in materials science. Among them, photomobile polymers (PMP), which are materials able to convert light energy into mechanical work, represent the ideal platform for the development of a large variety of touchless devices [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. In this work, we introduce a novel acousto-optic experimental setup in which small objects rotate around a single axis in space.…”