Photonic crystals - 3D printing for nanoscale coloringa

Synopsis

Controlling optical properties of materials is a new frontier that opened up in the last few decades. Already, laser engineering, fiber-optic cables, spectroscopy, revolutionised modern industry. However, nature already had the complete control over the light propagation in the form of photonic crystals. There are many notable examples of natural organisms employing photonic crystals to produce colorful patterns.  One of the recent scientific works demonstrates the ability to produce structural color within complex 3D objects at will. In this particular research, method of printing arbitrary colors in three dimensions at the microscopic length scale was introduced. 3D-printed polymer photonic crystals were heat-shrinked to achieve sub-100-nm features with a full range of colors. The technology promises the direct patterning and integration of spectrally selective devices.