Publications by authors named "Longfang Zou"

Implantable sensors provide long-term, accurate physiological measurements after a minimally invasive procedure, particularly when designed as transponders. Wireless interrogation of deeply implanted transponders with RF remains a challenge due to the high loss at the skin-air interface and large tissue RF absorption. This paper presents a system for wirelessly interrogating surface acoustic wave (SAW) sensors implanted in the main pulmonary artery (PA), where the pressure (PAP) is a very important parameter in the management of heart failure patients.

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We demonstrate a narrow-band plasmonic absorber based on a uniform array of nanoscale cylindrical dielectric resonators (DRs) on a metallic substrate at visible frequencies. Under a normally incident plane-wave excitation, the DRs resonate in their horizontal magnetic dipolar mode, which can be seen as localized plasmonic hot spots. Such a localized resonance also couples incident waves into surface plasmon polaritons (SPPs) bidirectionally, and perfect absorption is achieved by creating SPP standing waves.

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The concept of phase change material (PCM) based optical antennas and antenna arrays is proposed for dynamic beam shaping and steering utilized in free-space optical inter/intra chip interconnects. The essence of this concept lies in the fact that the behaviour of PCM based optical antennas will change due to the different optical properties of the amorphous and crystalline state of the PCM. By engineering optical antennas or antenna arrays, it is feasible to design dynamic optical links in a desired manner.

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Drawing inspiration from radio-frequency technologies, we propose a realization of nano-scale optical dielectric resonator antennas (DRAs) functioning in their fundamental mode. These DRAs operate via displacement current in a low-loss high-permittivity dielectric, resulting in reduced energy dissipation in the resonators. The designed nonuniform planar DRA array on a metallic plane imparts a sequence of phase shifts across the wavefront to create beam deflection off the direction of specular reflection.

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