[00932] Some recent advances on time-modulated metamaterials
Session Time & Room : 5B (Aug.25, 10:40-12:20) @D404
Type : Proposal of Minisymposium
Abstract : Time-modulated materials constitute the brand new class of metamaterials that is currently raising a huge interest in the mathematics, physics and engineering communities for their ability to achieve extreme wave phenomena. Indeed, by time modulating the properties (acoustic, optical, mechanical, etc.) of materials, one can, for instance, break reciprocity, achieve screening of parts of the domain by wave propagation, and reconfigure materials for optimization. The aim of this minisymposium is to bring together an interdisciplinary group of researchers to discuss the most recent results in the field and to favor interaction between theorists and experimentalists.
Organizer(s) : Kshiteej J. Deshmukh, Ornella Mattei
00932 (1/1) : 5B @D404 [Chair: Prof. Ornella Mattei]
[04433] Modeling Plasmons on Graphene with Time- and Space-Dependent Properties
Format : Talk at Waseda University
Author(s) :
Fadil Santosa (Johns Hopkins University)
Tong Shi (University of Minnesota)
Abstract : Graphene sheets are two-dimensional materials that are known to support plasmonic modes. The latter are electromagnetic waves which are concentrated near a surface and propagate along it. In graphene, these modes can exist on both sides of surfaces of the 2-D material. It has been shown that graphene sheets are effective in its ability to concentrate light, and for this reason, it is a candidate for photonic devices. In this work, we study graphene sheets which have time- and space-dependent properties. They are modeled as a flat conductive sheet with time- and space-dependent Drude weights. We show that in two dimensions, the governing equations can be reduced to a single 1-D time-dependent integro-partial-differential equation. The equation can be discretized and also solved approximately using perturbation arguments. We demonstrate the accuracy of the approximate solution and also show interesting behavior of the plasmons when the Drude weight is modulated temporarily and spatially.
[05163] Analytical and FDTD Modelling of EM Wave Interacting with Time-Varying Media
Format : Talk at Waseda University
Author(s) :
Debdeep Sarkar (Indian Institute of Science, Bangalore)
Abstract : First, we will focus on quasi-analytical ODE (ordinary differential equations) based methods to analyze velocity modulation imparted on EM (electromagnetic) waves interacting with infinitely extended time-varying medium. Later, we will examine EM wave interaction with finitely extended time-varying media using in-house Finite Difference Time Domain (FDTD) simulation methods. After critical observations on the generated reflection and transmission spectra of signals, we will comment on possible applications in next generation communication and Radar technologies.
[04583] Using Time-Varying Systems to Challenge Fundamental Limitations in Electromagnetics and Photonics
Format : Online Talk on Zoom
Author(s) :
Francesco Monticone (Cornell University)
Abstract : Time-varying systems offer opportunities for efficient electromagnetic and photonic devices, potentially surpassing various well-established theoretical limits, such as the Bode-Fano limit, the Chu limit, the Rozanov bound, delay-bandwidth limits, and others. At the same time, the characteristics of the temporal dimension create challenges and constraints that are unique to time-varying systems. In this talk, I will first review these opportunities and limitations, and will then discuss some of our recent research efforts in this area.
[03155] Energy conserving temporal metasurfaces
Format : Talk at Waseda University
Author(s) :
Kshiteej Jayendra Deshmukh (University of Utah)
Graeme W Milton (University of Utah)
Abstract : Changing the microstructure properties of a space-time metamaterial while a wave is propagating through it, in general requires addition or removal of energy, which can be of exponential form depending on the type of modulation.
This limits the realization and application of space-time metamaterials. In this work we present non-linear energy conserving temporal interfaces which address this problem.
