A Japanese research group announced that it has succeeded in laser oscillation by using a resonator based on 3D-structured photonic crystals.
The research group is led by Yasuhiko Arakawa, professor at the University of Tokyo. The details of the research was published on the Dec 12 edition of the online version of the Nature Photonics magazine.
Photonic crystals are artificial structures that can be described as photic semiconductors. While normal semiconductors consist of an array of atoms measuring about 10nm and electrons flowing on them, photonic crystals consist of artificial cyclical structures arranged at an interval of several hundred nanometers and light. What corresponds to semiconductor bandgap is called "photonic bandgap (PBG)."
Thus far, 2D-structured photonic crystals have mainly been researched. But, this time, the research group made a 3D-structured photonic crystal and confirmed that it confines laser light and brings about laser oscillation.
New photonic crystal made like plastic model
The new 3D-structured photonic crystal is made like a plastic model, Arakawa said. Parts of plastic models are cut off from a frame called "runner," and the 3D-structured photonic crystal is made by stacking 2D-structured parts separated from a runner.
The new photonic crystal is different from normal plastic models in that the parts of the photonic crystal are as small as 10 x 10μm and 150nm thick. By using an electron microscope, 25 parts are manually stacked (micro manipulation).
Because it requires high artisan skills, only one crystal can be made per day. And it can be made only by some members of the research group, Arakawa said. The current margin of error in position adjustment is 50nm.
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