Photothermal Response Characteristics of Host-Guest Liquid Crystals

Publisher Website
Google Scholar
Abstract
Photo-response properties in host-guest liquid crystals were investigated using a crystal rotation method combined with a pump and probe technique. The crystal rotation signals were in good agreement with the calculation results obtained using the Jones matrix analysis. Considering these experimental results and the relation between the polarization of the pump beam and the signal intensity, it is concluded that the photo-response properties can be explained by a change in the refractive index owing to temperature variation caused by laser light absorption. The refractive index change in host-guest liquid crystals sensitized at a He–Ne laser wavelength (632.8 nm) due to irradiation with a 20 mW of the pump beam (beam diameter was 740 µm) was estimated to about -0.004. The refractive index change was roughly proportional to the pump beam intensity. The change was reversible and the typical photothermal response time was less than 500 ms.