Conference Agenda

We employ an ab initio Maxwellian approach using quasinormal-mode theory to derive an "exact" Maxwell evolution (EME) equation for resonator dynamics. The new differential equation bears resemblance to the classical one found in coupled-mode-theory (CMT); however, it introduces novel terms embodying distinct physics, suggesting that the CMT predictions could be faulted by dedicated experiments. The new equation is anticipated to be applicable to all electromagnetic resonator geometries, and the theoretical approach we have taken can be extended to other wave physics.

Stimulated Raman scattering in transparent glass-ceramics (TGCs) based on bulk nucleating phase Ba2NaNb5O15 were investigated with the aim to explore the influence of micro- and nanoscale structural transformations on Raman gain. TGCs are composed of nanocrystals that are 10–15 nm in size, uniformly distributed in the residual glass matrix. A significant Raman gain improvement for both BaNaNS glass and TGCs with respect to SiO2 glass is demonstrated, which can be clearly related to the nanostructuring process.

We study coherent perfect absorption in organic microcavity resonators and extend these principles

and our findings to more complex microresonator systems that, beyond absorption, also possess additional cavity energy dissipation mechanisms. The experimental approach uses laser interferometry to closely monitor the energy fluxes within the system at all device ports as a function of the device geometry and the phase relationships of the incident beams. A particular focus is on optical systems based on 2nd order Bragg gratings, which are crucial for the operation of organic distributed feedback (DFB) lasers or as light incouplers in optical waveguiding films. Coherent control allows the diffraction efficiency of the underlying grating to be tuned over a wide range of values. This strategy allows significant optimisation of resonator structures for high efficiency light coupling in optical waveguides and fine tuning of grating parameters for the most efficient optical mode conversion.

With the development of compact optical devices, there is an increasing demand for the integrated photonic platform. Here, we fabricated planar resonant cavities for surface waves on one-dimensional photonic crystals, based on reverse design. The cavity is coupled to a linear waveguide. Experimental data proved the injection of Bloch Surface Wave (BSW) into the waveguide with a narrow bandwidth. Our work offers a platform to facilitate integration of single photon sources on BSW-based chips.

Chirality is characterized by the absence of mirror symmetry , it’s an intrinsic property of certain entities in the universe and influences molecular interactions and properties. Measure circular dichroism (CD) using a circular polarized light is a standard technique but its sensitivity is often limited. In this work , we explore extrinsic chirality, a property arising from asymmetric achiral materials , using a photo-acoustic spectroscopy. Photo-acoustic spectroscopy allows direct measurement of local absorption, by monitoring the heat produced and transferred to the surrounding air, regardless the transmitted, reflected, and scattered light that flows away from the sample. In conventional techniques, the CD is usually measured by taking into account only the extinction as transmitted (or reflected) light. In this study, we introduce a new PAS setup that employs an oblique-incidence laser to study extrinsic chirality of metasurfaces made of polystyrene nanospheres asymmetrically coated with Ag. Our experimental results reveal intriguing CD trends dependent on the angle of incidence and wavelength, indicative of extrinsic chirality. This study expands the application of PAS, enabling simultaneous analysis of multiple wavelengths and providing valuable insights into chiral metasurfaces.