The first motor rests on optically reducing the dielectric susceptibility, the second on reducing the ferro-electric polarisation. Non-linear absorption determines the dynamics by bleaching front propagation.
Motor 3 is an optical-to-mechanical converter, relying on a photo-mechanical force cycle or turbine. It is still work in progress and I only sketch the basic ideas.
In all cases the fundamental efficiency limits (Carnot?) still require evaluation, but it is possible to calculate the efficiencies of the motors as designed. They depend on material parameters, once geometry is optimised. In motors 1 and 2, they could range from about 2 - 7% for existing materials.
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