Science fiction is filled with interactive 3D holograms. They have been used in epic movies such as Star Wars and Avatar, but the challenge for Researchers is trying to turn them into reality by developing holograms that are sufficiently thin to work with advanced electronics.
Recently, a pioneering team led by RMIT University’s distinguished Professor Min Gu has developed a nano-hologram that is simple to create, can be viewed without 3D goggles and is 1000 times thinner than a human hair. This would be the world’s thinnest hologram paving the way towards the incorporation of 3D holography into daily electronics such as TVs, smartphones, and computers.
Conventional computer-generated holograms are too big for electronic devices but our ultrathin hologram overcomes those size barriers. Our nano-hologram is also fabricated using a simple and fast direct laser writing system, which makes our design suitable for large-scale uses and mass manufacture. Integrating holography into everyday electronics would make screen size irrelevant – a pop-up 3D hologram can display a wealth of data that doesn’t neatly fit on a phone or watch.
Professor Min Gu, RMIT University
Gu also said, "From medical diagnostics to education, data storage, defence and cyber security, 3D holography has the potential to transform a range of industries and this research brings that revolution one critical step closer.”
Conventional holograms control the phase of light to provide the illusion of 3D depth. But to produce adequate phase shifts, those holograms have to be at the thickness of optical wavelengths.
The RMIT research team, working together with the Beijing Institute of Technology (BIT), has shattered this thickness limit with a 25 nm hologram constructed on a topological insulator material – a novel quantum material that has the low refractive index in the surface layer but the ultrahigh refractive index in the bulk.
The topological insulator thin film serves as a central optical resonant cavity, which can improve the phase shifts for holographic imaging.
The next stage for this research will be developing a rigid thin film that could be laid onto an LCD screen to enable 3D holographic display. This involves shrinking our nano-hologram’s pixel size, making it at least 10 times smaller. But beyond that, we are looking to create flexible and elastic thin films that could be used on a whole range of surfaces, opening up the horizons of holographic applications.
Dr Zengji Yue, Co-Author
The research is published in the Nature Communications journal (DOI 10.1038/NCOMMS15354) on 18 May.