Advanced Optics and Nanophotonics

Nanophotonics stands at the forefront of modern science, providing exceptional tools to manipulate fundamental properties of light such as propagation, polarization, and intensity as well as the optical and electrical properties of materials at the nanoscale level.

In our lab, we combine high expertise in nanofabrication with the fundamental study and the control of light-matter interaction in coupled systems, that include photonic structures (metasurfaces, photonic crystal…) and low dimensional materials (quantum dots, nanowires, and thin films).

We currently focus on active metasurfaces made of perovskite films for lasing and directional emission control, light emitting transistor based on perovskite metasurfaces for the electrical control of the exciton-polariton framework, and strategies for metasurface-induced cooperative emission and superradiance in organic materials (J-aggregates).

These efforts aim to unlock new opportunities for designing next-generation optoelectronic devices and photonic systems.

Adv. Mater. 2022, 34, 2109157

Nano Lett. 2023, 23, 10, 4431–4438

Superconducting Nanowire Single-Photon Detectors

Superconducting nanowire single-photon detectors (SNSPDs) are among the most sensitive technologies for detecting individual photons, offering exceptional efficiency, high count rates, and low noise. Renowned for their superior performance in the infrared range, broadband operation, fast response times, precise timing resolution, and minimal noise levels, these detectors are heavily used in quantum photonic, imaging, LiDAR and deep space communication applications.

Our lab has developed end-to-end capabilities for SNSPD fabrication, from the growth of superconducting films to detector design, fabrication, and characterization. We are developing detector with additional functionalities such as spectral resolution, photon-number resolution, and polarization sensitivity by integrating SNSPDs with advanced optical structures, including metasurfaces, plasmonic elements, and multi-layer stacks. In parallel, we are focusing on scaling this cutting-edge technology by integrating SNSPDs into photonic circuits and exploring multiplexing schemes. To further enhance detector performance, we are investigating the microscopic mechanisms underlying SNSPD operation and exploring new high-temperature superconducting materials, such as MgB₂, which have the potential to revolutionize quantum detector technology by significantly reducing the cryogenic requirements.

Nanophotonics, 12, 3 (2023)

Materials Synthesis and NanoFabrication

Nanophotonics has undergone a remarkable transformation in recent years, driven by breakthroughs in material science, the refinement of nanofabrication techniques, and the precise manipulation of nanoscale light-matter interactions. Our research focuses on developing high-performance nanomaterials with tailored functionalities for light emission and detection. We exploit our expertise in synthesizing phase-change perovskite thin films for photonics and optoelectronics applications, fabricating color-tunable perovskite quantum dots for single-photon emission, engineering organic molecular aggregates, and depositing superconducting film for efficient single-photon detector technology (SNSPD).

Our labs offer state-of-art machines dedicated to material growth such as ultra-high vacuum magnetron sputtering, molecular beam epitaxy, thermal evaporators and atomic layer depositing; and to nanofabrication such as electron-beam lithography, focus ion beam, plasma etching.

Our efforts push the boundaries of photonic innovation, enabling novel applications across a range of cutting-edge technologies with real-world applications.

SEM picture of NbTiN superconducting nanowire growth and fabricated in our lab

Undergraduate Projects

Balloon-Drone for Volcano Surveillance (2018)

Autonomous glider drones are employed for aerial monitoring of volcanic eruption, but conventional methods of drone deployment require the gliders to gain altitude independently, substantially reducing their autonomous flight time (which in the absence of thermals can fall below 30 minutes). In this PS9888 (Making and Tinkering) module, we wanted to use a weather balloon to provide uplift for the surveillance glider to a drop altitude of ~4000 m. We designed a release system that detaches the glider from the balloon upon reaching the specified altitude and expect that this method would allow extending volcano surveillance missions to one hour or more - a huge improvement from the flight time of a glider without balloon assistance.

Solar Ornithopter (2016)

In this PS9888 (Making and Tinkering) module, we wanted to integrate flexible solar cells on the wings of a robotic ornithopter (a robot that flies like a bird), to recharge its batteries. We designed an ornithopther with oversized wings to increase surface area, and obtained polymer solar foils from infinityPV, with nominal power conversion efficiency of 5%. We tested and increase in battery duration of approximately 20%, meaning that next flexible solar cell technologies, such as hybrid organic inorganic perovskite cells with target efficency of 20%, could enable completely self-powered ornithopters.

Space Balloon(2015)

In this PS9888 (Making and Tinkering) module, we wanted to test frinGOe - an innovative optical spectrometer, in extreme environmental conditions, as well as a number of tracking and sensing systems for high altitude balloons. We succesfully launched and retrieved 3 helium balloons in Australia, which reached peak altitude of about 30 Km before falling back on Earth! For more information, follow the NTU High Altitude Balloon project on Facebook and see the photogallery of our adventure on Flickr!

Optical Spectroscopy of Nanomaterials Cesare Soci SitesGo OSON Research

Unseen Light (2014)

In this collaborative project with students from the Photography and Digital Imaging Program at the School of Art, Design and Media, we created an exhibition where photography ran alongside the scientific laboratories at the School of Physical and Mathematical Sciences. Just as scientists explore unusual aspects of light, the artists utilize non-conventional visual methods to explore and re-imagine spaces and invent new perspectives. Through the use of techniques such as pinhole cameras, digital imaging, large-format photography and other unorthodox materials, these artists gave inspirations to a new refreshing array of possibilities in interdisciplinary research between art, photography, and the physical sciences. See the photogallery of the opening event.