Controllable tuning of Fabry–Perot cavities via laser printing†
The Fabry–Perot (FP) cavity is one of the basic optical components that has been widely applied in interferometry, spectroscopy, lasers and optoelectronic devices. Currently, tailorable FP cavities are highly desirable for fast and in situ modulation, which is crucial for optoelectronic devices and their integration. Here a simple tuning strategy of FP cavity mode is developed based on the plasmon-assisted laser printing technique. The laser irradiation induces photochemical and/or photothermal degradation of the polymer medium in the cavity, which is highly dependent on the film thickness and laser power. Thus, the FP cavity mode can be precisely and continuously tuned with irradiation time, which is then monitored using reflection spectra. Such a laser printing strategy is facile and general, which is capable of generating different structural colours.