Picosecond mode switching and Higgs amplitude mode in superconductor-metal hybrid terahertz metasurface

Mode Switching

In many control applications, a speciic set of output tracking controllers of satisfactory performance have already been designed and must be used. When such a collection of control modes is available, an important problem is to be able to accomplish a variety of high level tasks by appropriately switching between the low-level control modes. In this paper, we deene a concept of control modes, ...

Mode Switching in Causally Dynamic Hybrid Bond Graphs

The Causally Dynamic Hybrid Bond Graph is extended to the case of modeswitching behaviour. Mode-switching ‘trees’ of switches and elements are historically used by bond graph practitioners to represent elements with piecewise-continuous functions. This case is defined as ‘parametric switching’ for the purposes of the hybrid bond graph, since the switching is internal to the element, as opposed ...

Whispering-gallery mode terahertz pulses.

We report what is to our knowledge the first observation of a subpicosecond terahertz (THz) pulse propagating as a superposition of the whispering-gallery modes (WGMs) of a dielectric cylinder. The WGM THz pulses are coupled into and out of a 5-mm-diameter silicon cylinder via a 100-mum -thick, single-mode silicon slab waveguide. We observed two round-trip cylindrical cavity pulses from this co...

Optimizing broadband terahertz modulation with hybrid graphene/metasurface structures.

We demonstrate efficient terahertz (THz) modulation by coupling graphene strongly with a broadband THz metasurface device. This THz metasurface, made of periodic gold slit arrays, shows near unity broadband transmission, which arises from coherent radiation of the enhanced local-field in the slits. Utilizing graphene as an active load with tunable conductivity, we can significantly modify the l...

Protection Switching ( APS ) Mode