Holograms have fascinated onlookers for over half a century. But the devices for producing these holographic images have been relatively bulky contraptions, forced into their large size in part by the wavelengths of light that are necessary to generate them.
Emerging technologies such as plasmonics and metamaterials have offered a way to manipulate light in such a way that these wavelengths can be shrunk down. This makes it possible to use light for devices such as integrated photonic circuits. And just this week, we’ve seen metasurfaces enable an elastic hologram that can switch images when stretched.
Now, a team of researchers at RMIT University in Melbourne Australia and the Beijing Institute of Technology has developed what is being described as the “world’s thinnest hologram.” It is only 60 nanometers thick; they produced it not by using either plasmonics or metamaterials, but with topological insulators. The resulting technology could enable future devices capable of producing holograms that can be seen by the naked eye, and are small enough to be integrated into our mobile devices.