Special Sessions

The Congress holds Special Sessions, comprised of invited and contributed papers, on areas deemed to be topical and of special interest to conference attendees.

This year, submissions will be open for the following special sessions:

Exceptional Points of Degeneracy (Organized by Filippo Capolino)
Exceptional points of degeneracy in electromagnetic/photonic systems is an important emerging topic that has been receiving increasing attention in the past few years. An exceptional point is a very special degeneracy condition of at least two eigenmodes of a system made of multimode resonators, waveguides, or including coupling to other oscillating systems, also of quantum mechanical nature. Beside the interesting physics behind this phenomenon and the engineering challenges to realize such points in realistic structures, various applications have also been proposed, ranging from lasers and oscillators, dispersion engineering, to extremely sensitive sensors.
In this session we collect some of the most active speakers in that area providing also a good representation of the general activity in the field.

Confirmed invited speakers: 
- Demetrios Christodoulides, "Parity-Time Symmetry and Exceptional Points in Optics"
- Tsampikos Kottos, "Exceptional Point Degeneracies in Micro-mechanical Structures: Theoretical Challenges and Technological Applications"
- Che Tin Chan, "Exceptional Arcs and Cusps"
- Jan Wiersig, "Hamiltonian and Liouvillian Exceptional Points in Noisy Non-Hermitian Systems"

Fundamental Performance Limits in Photonics (Organized by Owen Miller, David Miler, and Francesco Monticone)
This session highlights the growing research field centered around identifying the extreme limits of classical and quantum interactions of light with matter. From fundamental constraints of electrodynamics—causality, linearity, energy conservation, reciprocity, coupling sum rules, and information/entropy flow—it is now becoming possible to discover general bounds that represent the best achievable response, whether in a Silicon chip, a large-area metasurface, or a quantum-optics experiment. A bounds-first approach to photonic design accelerates innovation: global bounds give size and material guidelines for designs, identify applications for which current devices are already operating close to their limits, and suggest opportunities for orders-of-magnitude improvement over the current state of the art.

Confirmed invited speakers: 
- Owen Miller, "Identifying and Approaching Fundamental Limits in Nanophotonics and Beyond"
- Jelena Vuckovic, "Scalable Photonics: an Optimized Approach"
- Jacob Khurgin, "Light-Matter Interaction Time as the Defining Factor in Photonics"
- David Miller, "How to Count Modes and Deduce Limits in Optics"
- Mats Gustafsson, "Fundamental Limits for Electromagnetic Systems"
- Alejandro Rodriguez, "Fundamental Nanophotonics Limits via Lagrange Duality"

High-refractive-index dielectric nanophotonics (Organized by Søren Raza)
Dielectric optical materials with a high refractive index are receiving increasing attention in the nanophotonics research community. When structured on the nanoscale, these materials display a diverse set of low-loss optical resonances, such as Mie resonances, which facilitate efficient control over both near- and far-field properties of light. These desirable properties are currently being exploited for a wide range of applications, such as light emission, sensing, nonlinear optics, and tunable metasurfaces.This Special Session is dedicated to the latest advancements within nanoscale optics using high-refractive-index dielectric materials.

Confirmed invited speakers: 
- Arseniy Kuznetsov, "Active Dielectric Nanoantennas and Metasurfaces"
- Isabelle Staude, "Active Tuning of Mie-Resonant Dielectric Metasurfaces"
- Dragomir Neshev, "High-Refractive_Index Nnlinear Dielectric Metasurfaces"
- Andrey Miroshnichenko, "Boosting the Quality Factor of a Single Subwavelength Particle"
- Nicolas Bonod, "Mie-Resonant Light Scattering and Times Dynamics of Dielectric Cavities"

Topological Photonics (Organized by Ranjan Singh)
Topological photonics is an emerging area of research where the geometrical and topological ideas are being applied to design and control the behavior of light which is vital for various potential applications like high-speed photonic interconnects to robust lossless waveguides. Drawing inspiration from condensed matter physics, the introduction of topology endows the photonic systems with unprecedented functionalities such as unidirectional propagating edge states and immunity towards defects or impurities. Topology, as new research perspective in photonics, is not only expected to bring the remarkable changes in the field of integrated photonics and optical interconnects but also enable the exploration of various fundamental phenomena such as lasing, phonon-photon interactions and quantum photon-pair generation in topologically nontrivial photonic structures

Confirmed invited speakers: 
- Junsuk Rho, "Photonic Crystals and Metamaterials Towards 2D and 3D Topological Phases"
- Mario Silverinha, "A Time-Crystal Model of the Electron Spin"
- Cesare Soci, "Controlling the Circular Photogalvanic Effect in Topological Insulator Metamaterials"
- Mikael Rechtsman, "Nonlinear Aspects of Topological Photonics"
- Maxim Gorlach, "Detection of the Two-Photon Topological Phase in the Inversion-Symmetric Interacting Dissipative Systems"
- Alexander Szameit, "Nonlinear Photonics Topological Insulators"

Tunable Metasurfaces (Organized by Arseniy Kuznetsov)
Metasurfaces, as two-dimensional analogues of metamaterials, have recently emerged as a hot research topic giving huge promise for multiple future applications. Due to their ability to precisely control light amplitude and phase at nanometer scales and resolution the metasurfaces have an opportunity to revolutionize optics by bringing forward new multifunctional and compact flat optical components, which can be simply manufactured using conventional semiconductor foundries. While many applications of metasurfaces for replacing conventional optics are already under development, many future optics and photonics technologies, such as AR/VR, LiDAR, Holographic displays etc., require tunable wavefront control down to sub-wavelength scales. This motivates development of novel types of tunable metasurfaces, where the light phase and amplitude can be dynamically controlled down to individual pixel. Solving this challenging problem requires combined research expertise in nanophotonics, electronics and material science. In this session, we will discuss the recent progress in this highly dynamic field of tunable metasurfaces and draw a perspective for their future technological applications.

Confirmed invited speakers: 
- Harry Atwater, "Metasurface Laser Lightsails"
- Ramon Paniagua Dominguez, "Dynamic Control of Light Wavefronts with Tunable Dielectric Metasurfaces"
-  Romain Quidant, "Active Dielectric Meta-Optics"
- Jon Schuller, "Reconfigurable Metasurfaces with Classical and Quantum Metal-Insulator Transistions"
- Jason Valentine, "Dynamic Optical Metasurface Based on Phase Change Media"