Topology and new interaction regimes between light and matter in nanoscale photonic systems
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Abstract
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Transferring physical traits from radiation to matter and vice versa has driven many scientific and technological revolutions in the last century. In this context, exchanging topological traits, i.e. geometrical properties in real or synthetic space, could also be considered as an avenue for new applications and discoveries. Although topological properties of electromagnetic fields have been a source of avid research in the last few decades, understanding how the topology of light transfers in a classical or quantum interaction with matter is still at its infancy. This is especially true considering how most light-matter interactions occur at the nanoscale, where only specific light-matter interaction regimes apply and where the topological properties of light are not well understood. In this seminar, I will present our discovery of new topological properties for light at the nanoscale and examine their transfer to matter via classical and quantum interactions, in different interaction regimes. I will begin by presenting our experimental exploration of the spin-orbit interaction (SOI) of light in plasmonic lattices, which led to the discovery of optical skyrmions – three-dimensional topological defects, initially predicted in the field of high-energy physics. I will highlight special cases for optical manipulation of matter arising in such systems, and further dive into higher-dimensional light topology, manifesting in quasi-periodic lattices. Lastly, I will show a new method for performing spatial modulation of free electron beams using light, including new interaction regimes we achieved experimentally for the first time, where light's topology can, in some cases, be imbued onto the electrons.
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About the Speaker
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Dr. Shai Tsesses is a postdoctoral associate at the MIT–Harvard Center for Ultracold Atoms, working with Prof. Vladan Vuletić. At MIT, he is leading a team developing the next generation of neutral atom quantum processors, able to implement deep and high-fidelity quantum circuits. Dr. Tsesses earned his Ph.D. in Electrical Engineering from the Technion–Israel Institute of Technology, where he made key experimental contributions to topological and quantum nano-photonics, as well as free-electron–light interactions. His research explores the frontiers of light–matter interaction, bridging atomic physics, electron beam physics, and quantum information science. He has authored more than 30 publications in leading journals such as Science and Nature, and is a recipient of numerous fellowships and awards, including the Rothschild and Adams Fellowships, as well as the OPTICA Tingye Li Innovation Prize.