A nanostructure design enables pixels to produce two different colors depending on the polarization of the incident light
Through precise structural control, A*STAR researchers have encoded a single pixel with two distinct colors and have used this capability to generate a three-dimensional stereoscopic image1.
Figuring out how to include two types of information in the same area was an enticing challenge for Xiao Ming Goh, Joel Yang and their colleagues at the A*STAR Institute of Materials Research and Engineering. They knew such a capability could help a range of applications, including ultrahigh-definition three-dimensional color displays and state-of-the-art anti-counterfeiting measures. So they set about designing a nanostructure architecture that could provide more ‘bang for the buck’.
Having previously used plasmonic materials to generate color prints at the optical diffraction limit by carefully varying the nanostructure size and spacing, Yang thought polarization would be a promising direction to pursue. “We decided to extend our research to prints that would exhibit different images depending on the polarization of the incident light,” he explains.
The main challenge to overcome was the mixing of colors between polarizations, a phenomenon known as cross-talk. Goh and Yang trialed two aluminum nanostructures as pixel arrays: ellipses and two squares separated by a very small space (known as coupled nanosquare dimers).
Each pixel arrangement had its own pros and cons. While the ellipses offered a broader color range and were easier to pattern than the nanosquare dimers, they also exhibited a slightly higher cross-talk. In contrast, the coupled nanosquare dimers had a lower cross-talk but suffered from a very narrow color range.
Because of their lower cross-talk, the coupled nanosquare dimers were deemed better candidates for encoding two overlaid images on the same area that could be viewed by using different incident polarizations.
While the coupled nanosquare dimers’ color palette could be expanded by varying the width and spacing between adjacent squares in each nanosquare dimer, the ellipses were better for demonstrating the wide color range achievable.
Furthermore, the researchers used these pixel arrays to generate a three-dimensional stereoscopic image. They achieved this by using ellipses as pixel elements, carefully offsetting the images and choosing background colors that minimized cross-talk.
“Being able to print two images onto the same area and, further, generating a three-dimensional stereoscopic image opens up many new avenues for applications,” remarks Goh.
But the possibilities do not end there. Complex nanostructures, including circularly asymmetric shapes, offer many more options. “By employing additional circular polarizations, we could encode multiple images ― that is, not just two, but three or more images in a single area,” Goh explains.
The A*STAR-affiliated researchers contributing to this research are from the Institute of Materials Research and Engineering. More information about the group’s research can be found at the Plasmonic and Semiconductor Nanostructures Laboratory webpage.
Goh, X. M., Zheng, Y., Tan, S. J., Zhang, L., Kumar, K., Qiu, C.-W. & Yang, J. K. W. Three-dimensional plasmonic stereoscopic prints in full colour. Nature Communications 5, 5361 (2014). | article
Scientists channel graphene to understand filtration and ion transport into cells
11.12.2017 | National Institute of Standards and Technology (NIST)
Successful Mechanical Testing of Nanowires
07.12.2017 | Helmholtz-Zentrum Geesthacht - Zentrum für Material- und Küstenforschung
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
14.12.2017 | Health and Medicine
14.12.2017 | Physics and Astronomy
14.12.2017 | Life Sciences