The present invention relates to nanoprocessing and heterostructuring of silk. It has been shown that few-cycle femtosecond pulses are ideal for controlled nanoprocessing and heterostructuring of silk in air. Two qualitatively different responses, ablation and bulging, were observed for high and low laser fluence, respectively. Using this approach, new classes of silk-based functional topological microstructures and heterostructures which can be optically propelled in air as well as on fluids remotely with good control have been fabricated.

A method for fabrication of free standing mechanical and photonic structures is presented. A resist mask is applied to a bulk substrate. The bulk substrate is attached to a movable platform. The bulk substrate is exposed to an ion stream produced by a reactive ion beam etching source. The platform is moved relative to the ion stream to facilitate undercutting a portion of the bulk substrate otherwise shielded by the mask.