Observation of Self-Trapping of Light in a Self-Written Channel in a Photosensitive Glass

Observation of light-induced refractive index reduction in bulk glass and application to the formation of complex waveguides

“…Here two differential equations [1] are used where the paraxial wave equation describes the propagation of light (in the direction z) and the photosensitivity equation describes the change in refractive index (∆n) in response to light (Table 1). Previously a simple model has been shown to agree well with experiments in germanosilicate [2] and chalcogenide glass [3], and in photopolymers [4]. Here we modify this model to describe a decrease in index in response to light.…”

“…If the index of the material increases in response to illumination, this area of higher index reduces the diffraction of the incoming beam and over time a self-written channel waveguide can evolve [1,2,3]. These waveguides offer a number of advantages in comparison with other methods of fabricating waveguides such as epitaxial growth, diffusion methods and direct writing.…”

“…Also, these waveguides evolve dynamically, and they experience minimal radiation losses due to the absence of sharp bends. Previously, increases in index have been used to self-write channel waveguides in bulk photopolymers [4,5] and in glass in the planar geometry [2]. Recently we showed the first self-writing effects in bulk chalcogenide glass [3].…”

Optical Nanocomposites Based on High Nanoparticles Concentration and Its Holographic Application

“…For example, in cited work the results of light self-focusing and self-written waveguide preparation process obtained on glass light sensitive materials are summarized [21].…”

Exploration of self-writing and photosensitivity in ion-exchanged waveguides

“…[1][2][3] A Gaussian beam focused onto a photosensitive sample initially diffracts, and since photosensitive index changes occur more rapidly where the intensity is high, the material undergoes the fastest changes at the input face and along the propagation axis. In many materials light causes the index to increase, which reduces the initial diffraction of the Gaussian writing beam.…”