Pai-Yen Chen

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We propose and analyze a graphene-based cloaking metasurface aimed at achieving widely tunable scattering cancelation in the terahertz (THz) spectrum. This 'one-atom-thick' mantle cloak is realized by means of a patterned metasurface comprised of a periodic array of graphene patches, whose surface impedance can be modeled with a simple yet accurate(More)
(2012). Boosting optical nonlinearities in ε-near-zero plasmonic channels. Abstract The anomalous transmission properties of zero-permittivity ultranarrow channels are used to boost Kerr nonlinearities and achieve switching and bistable response for moderate optical intensities. Strong field enhancement, uniform all along the channel, is a typical feature(More)
Following our recently introduced analytical tools to model and design conformal mantle cloaks based on metasurfaces [Padooru et al., (2012)], we investigate their performance and physical properties when excited by an electric line source placed in their close proximity. We consider metasurfaces formed by 2-D arrays of slotted (meshes and Jerusalem cross(More)
spatial profi le. Gradient metasurfaces provide a much richer control of the wave-front in both local amplitude and phase of the emerging transmitted and refl ected beams. [ 4–7 ] Such structures enable fl at optical components for beam focusing, polarization control and phase correction, to name a few examples. [ 4–9 ] The next challenge and exciting(More)
Graphene, a one-atom-thick carbon sheet with electronically tunable electromagnetic properties, has an interesting terahertz response, currently explored in a variety of applications. In this work, we put forward the design and realization of graphene nanodevices for THz phase modulation and beamforming, of large interest to sensing and wireless(More)
Miniaturized helix antennas are integrated with drug reservoirs to function as RFID wireless tag sensors for real-time drug dosage monitoring. The general design procedure of this type of biomedical antenna sensors is proposed based on electromagnetic theory and finite element simulation. A cost effective fabrication process is utilized to encapsulate the(More)
A dual band electrically small folded ellipsoidal helix antenna (EHA) is designed for the wireless data communication and wireless power transferring functions of an artificial cardiac pacemaker. In this design, a spatially non-uniform pitch ellipsoidal helix structure is used to tune the dual resonant frequencies to the desired bands at 900 MHz and 2.4(More)
We put forward here design and semiclassical modeling of nonlinear and reconfigurable optical metasurfaces formed by arrayed nanoantennas with nano/subnano-scale feed-gaps, where the photon-assisted tunneling results in a set of linear/nonlinear quantum conductivities. We show that optical nonlinearities sourced from higher-order quantum conductivities may(More)
Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS)(More)