Researchers have developed a tiny, room-temperature device that creates a special type of structured light called radially polarized photons, which are highly useful for secure communication, advanced imaging, and precision optical tools. By carefully designing and positioning a quantum dot within a nanoantenna, they achieved high-quality light with over 93% polarization purity. This breakthrough helps improve the efficiency and practicality of devices that use structured light, paving the way for advancements in communication and optical technology.
A team led by Prof. Ronen Rapaport from the Racah School of Physics at The Hebrew University of Jerusalem has developed a new device that produces radially polarized photons at room temperature. This advancement offers new possibilities for both classical and quantum communication technologies.
Radially polarized light has a unique electric field structure that makes it useful for a range of applications, including secure communication, advanced imaging, and precision optical tools. Producing this type of light reliably, especially in nano-photonic systems, has been a technical challenge.
The team addressed this challenge by combining a “giant” CdSe/CdS colloidal nanocrystal (about 20 nanometer in diameter) with a hybrid metal-dielectric nanoantenna. The quantum dot is precisely placed on a tiny metal nanocone at the center of the antenna, which allows the device to generate photons with a radial polarization purity of more than 93%. The system works efficiently at room temperature and is only 10 microns wide, compact enough for potential integration into on-chip technologies.
“The accurate positioning of the quantum dot plays a key role in achieving high-quality light output,” said Prof. Rapaport. “This study helps us better understand how to control light polarization in small-scale devices, which is important for future quantum applications.”
The research combines experimental data and simulations to provide insights into how nanostructures can enhance photon emission and polarization. These findings may help advance the design of nano-photonic devices for use in secure communication and other emerging technologies.
The research paper titled “Ultrafast and Highly Collimated Radially Polarized Photons at Room Temperature from a Colloidal Quantum Dot Coupled to a Hybrid Nanoantenna” is now available in ACS Photonics and can be accessed at https://pubs.acs.org/doi/full/10.1021/acsphotonics.4c01516
Researchers:
Alexander Nazarov1, Yuval Bloom1, Boaz Lubotzky1, Hamza Abudayyeh2, Annika Mildner3, Lorenzo Baldessarini4, Yuval Shemla1, Eric G. Bowes5, Monika Fleischer , Jennifer A. Hollingsworth5, Ronen Rapaport1
Institutions:
- Racah Institute of Physics, Hebrew University of Jerusalem
- Department of Physics, University of Texas at Austin
- Institute for Applied Physics and Center LISA, University of Tuebingen
- Department of Physics, Trento University
- Materials Physics & Applications Division: Center for Integrated Nanotechnologies
The Hebrew University of Jerusalem is Israel’s premier academic and research institution. With over 23,000 students from 90 countries, it is a hub for advancing scientific knowledge and holds a significant role in Israel’s civilian scientific research output, accounting for nearly 40% of it and has registered over 11,000 patents. The university’s faculty and alumni have earned eight Nobel Prizes, two Turing Awards a Fields Medal, underscoring their contributions to ground-breaking discoveries. In the global arena, the Hebrew University ranks 81st according to the Shanghai Ranking. To learn more about the university’s academic programs, research initiatives, and achievements, visit the official website at http://new.huji.ac.il/en