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Laser-pointer-induced self-focusing effect in hybrid-aligned dye-doped liquid crystals

Research output: Contribution to journalArticleScientificpeer-review

Details

Original languageEnglish
Article number9890
Number of pages7
JournalScientific Reports
Volume5
DOIs
Publication statusPublished - 6 May 2015
Publication typeA1 Journal article-refereed

Abstract

Nonlinear optics deals with phenomena where "light controls light"; e.g., there is mediation by an intensity-dependent medium through which light propagates. This field has attracted much attention for its immense potential in applications dependent on nonlinear processes, such as frequency conversion, multiple-photon absorption, self-phase modulation, and so on. However, such nonlinearities are typically only observed at very high light intensities and thus they require costly lasers. Here, we report on a self-focusing effect induced with a 1 mW handheld laser pointer. We prepared polymer-stabilized dye-doped liquid crystals, in which the molecular director orientation gradually changes from homeotropic at one surface to homogeneous at the other. This is referred to as hybrid alignment. In such films, the threshold intensity needed to form diffraction rings was reduced by a factor of 8.5 compared to that in conventional homeotropic cells, which enabled the induction of the self-focusing effect with a laser pointer.

Keywords

  • ORIENTATIONAL OPTICAL NONLINEARITY, GENERATION, STORAGE, LIGHT

Publication forum classification

Field of science, Statistics Finland