Development of techniques for characterization of extremely thin films is an important challenge in terahertz (THz) science and applications. Spectroscopic measurements of materials on the nanometer scale or of atomic layer thickness (2D materials) require a sufficient terahertz wave–matter interaction length, which is challenging to achieve in conventional transmission geometry. Waveguide-base...

in this paper, a new algorithm for studying elastic wave propagation in the phononic crystals is presented. at first, the displacement-based forms of elastic wave equations are derived and then the forms are discretized using finite difference method. so the new algorithm is called the displacement-based finite difference time domain (dbfdtd). three numerical examples are computed with this met...

wave prediction is useful for safety and effective management of vessel navigation or construction of offshore structures. since human activity mainly takes place in nearshore regions, accurate wave prediction is necessary there. however, nearshore waves are not easy to predict compared with ocean waves, because not only the waves but also the wind, which is the energy source of the waves, chan...

An interpretation of focusing and image formation on scattering of electromagnetic waves by a dielectric cylinder (a cylindrical lens) is proposed on the basis of the full Maxwell theory. It is centered on analysis of the behavior of integral curves of the Poynting vector here called wave rays. These wave rays cannot intersect so that the focusing and imaging spots are identified with regions o...

A new method of designing horn-fed frequency scanning holographic antenna is proposed. The artificial surface design of holographic antenna is based on generalized law of reflection. The input admittance is utilized to construct the interference pattern of the surface which is intervened by the excitation wave and the required radiation wave. The scalar admittance unit cell which is composed of...

Most of the optical sensors based on surface plasmon resonance (SPR) are imitated from two main configurations. Firstly, in the KretschmannRaether configuration, a thin metal layer is sandwiched between the prism and the air. Otherwise, the Otto configuration, there is a gap between the metal and the prism. However, the Kretschmann-Raether geometry is more conventional scheme to generate the su...

Optical transfer function (OTF) and image spectrums of the layered metal (M)–dielectric (D) superlenses (MD)n (where n is the number of cycles) are analyzed via transfer matrix method and effective-medium model. It is shown that the magnitude of OTF (MTF) with a high cutoff wave vector does not guarantee high resolution; the fluctuation of phase of OTF (PTF) is also a prime factor causing super...

The millimeter-wave front-end module for an automotive radar sensor is generally composed of an antenna placed on the front surface of the sensor head and a millimeter-wave circuit inside it. As the antenna for the radar sensor, several types of antennas, a slotted waveguide antenna, a triplate antenna, a dielectric lens antenna, a dielectric leaky wave antenna and a microstrip antenna, have be...