Hologram messaging is a sci-fi staple that has captured people's collective imaginations for years.
Now, in what could be a fascinating example of sci-fi made into reality, Missouri University of Science and Technology researchers have devised a method that they say could be used to create smartwatches with efficient holographic displays, among other applications.
Ion beam milling
The Missouri S&T team of researchers demonstrated their new concept built using impressive nanotechnology; their method uses a single two-dimensional material monolayer with a thickness of less than one nanometer.
Published in Nano Letters, the researchers' paper, titled "Atomically thin nonlinear transition metal dichalcogenide holograms," details the optical holograms they created. The researchers devised "a prototype device by reconstructing several kinds of holographic images with tungsten disulfide monolayers of the thickness of around 0.7 nanometer."
For context, a nanometer is equivalent to one billionth of a meter, and a tungsten disulfide monolayer only contains one layer of tungsten atoms sandwiched between two layers of sulfur atoms.
The holograms are created using only a single nanopatterned tungsten disulfide monolayer that is able to control the wavefront of light. Here, the designed hologram patterns are punctured by a nanofabrication process known as focused ion beam milling.
In their research, the Missouri S&T team demonstrated holographic images of the Chinese character for the word “light” with blue and green colors.
The team believes the new technology can be utilized in the future to create impressive technologies. For example, security markings on banknotes and credit cards could be made using the nanotechnology.
They also say it could be used for optical communications, data storage, and holographic smart device displays.
Higher conversion efficiency
“We are able to control the binary amplitude modulation of zero and one by simply etching out or keeping the tungsten disulfide monolayer area,” Dr. Xiaodong Yang, an associate professor in mechanical and aerospace engineering at Missouri S&T said in a press release.
In addition, Yang says their new findings present a significant improvement on existing holographic technology.
“Our holograms possess significantly higher nonlinear conversion efficiency than the currently existing plasmonic metasurface holograms made of metallic nanostructures.”
While it may be a while before we see the benefits of the research in the real world, being able to watch video messages with hologram displays would be an impressive example of science fiction made into reality.