title: Optical bistability by photothermal displacement in prism coupling into planar waveguides.
abstract: We have identified photothermal displacement as a mechanism for optical bistability (OB) in prism coupling into absorbing planar waveguides: heating by the absorbed incoupled power causes a buckling of the waveguide, a reduction in air-gap width, and thus an increase in incoupling efficiency and a positive feedback. We developed a theory of this OB that qualitatively agrees well with experimental results obtained by coupling argon-laser light into indium-tin oxide layers as strongly absorbing waveguides. This new OB is quite different from dispersive OB in prism or grating couplers caused by a power-dependent effective guide index.
authors.forename: W
authors.initials: W
authors.lastname: Lukosz
authors.forename: P
authors.initials: P
authors.lastname: Pirani
authors.forename: V
authors.initials: V
authors.lastname: Briguet