Visible-light modulators and power limiters based on spin crossover material thin films

We review our recent studies on visible-light modulators exploiting a relatively uncommon yet attractive family of phase change materials, the spin crossover molecular complexes. In particular, we report different embodiments, based on thermally-activated thin films of the evaporable iron 1,2,4,-triazolyl borate compound, that have been successively designed and fabricated to obtain proof-of-principle demonstrators but also devices with enhanced modulation depth and spectral bandwidth. We show that the response of the components can be affected by self-heating, leading in turn to optical power limiting behaviour.