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We propose an innovative cloak to enable different sizes, shapes and also constituent parameters of arbitrary hidden objects not only to observe the fields with 360-degree eyesight from the environment outside the cloak but also to need neither to be ‘custom-made’ nor to be confined by the position of the corresponding anti-objects. We design the spatially varying constituent parameters of an innovative cloak by the aid of transformation optics with two steps of coordinate transformations and testify the performances of an innovative cloak by COMSOL simulation software. Herein, we demonstrate the corresponding Ez field distribution as a testimony of invisible hidden objects and claim that the simulation results demonstrate a good agreement with analytical study of an innovative cloak.

Slowing light has arisen increasing attentions due to its applications for optical switching, optical hard disk and enhanced photon-matter interaction, especially the system utilizing left-handed tapered waveguide (LHWG) to demonstrate either oscillatory mode or surface plasmon polariton (SPP) mode which are the most possible candidates to be commercialized. But both of them suffer from the loss coming from metal to limit the time to trap photons in the LHWG. Hence, we hire highly contrast dielectric metamaterials as LHWG to reduce the Ohmic loss from metal and demonstrate slowing light effect. Our results are confirmed by introducing E-field (or H-field) distribution and power flow recording in CST simulation software.

By introducing both cavity mode and plasmonic resonance simultaneously in the designed sandwiched metamaterials, we present a scalable bandpass filter to demonstrate ultra-wide bandwidth, excellent efficiency and sharp band-edge transition. Our results show that this bandpass filter possess ultra-wide bandwidth (UWB) of 20 GHz centered at 60.5 GHz, with almost zero reflectance (0.0042) and present transitions within 0.6 GHz from -3dB to -20dB for upper and lower transmittance band-edge transition. Such an UWB bandpass filter is applicable for the commercialized unlicensed 60 GHz spectrum with a bandwidth exceeding 9 GHz, an unanswerable question for conventional passive bandpass filters to possess wide bandwidth and high quality factor simultaneously.