“…To be useful practically in all-optical switching, nonlinear media must simultaneously satisfy three main requirements: large nonlinear refractive index (n 2 ) at the operating wavelength; minimal absorption due to one or multiphoton absorption; and ultrafast nonlinear refractive index response and relaxation times. [1][2][3] Recently, many materials for optical switching devices have been reported, including inorganic and semiconductor materials, 4-6 multiple quantum wells, 7,8 liquid crystals, 9,10 organic compounds 11,12 and polymers. 13,14 In the present study, we chose erythrosine B based poly (methacrylate) films with different chain lengths of methytlene group as the sample, and investigated experimentally the optical switching and beam deflection effects of these polymers under a CW pump beam.…”