Laser switching and characterisation of chalcogenides: systems, measurements, and applicability to photonics [Invited]

The objective of this paper is to review the characterisation methods and procedures used to laser switch phase change materials, and then assess their applicability for characterising phase change materials for active photonics devices. Specifically we characterise the performance of our pump-probe laser system and compare it with other 'static' and 'dynamic' testers. Our pump-probe system was developed to measure the phase transformation kinetics of chalcogenide films by simultaneously measuring the transmission and reflection of a probe laser with a temporal resolution of 1 ns. We also use the system to measure the second order nonlinear refractive index of chalcogenide thin films. Laser switching of chalcogenides are efficient methods to screen new materials but the switching time seems to have a strong dependence on the measurement method and procedure. Therefore in this article we recommend bespoke methods and procedures for assessing the performance of new chalcogenide compositions for specific photonic devices. (C) 2017 Optical Society of America