We study the beaming effect of light for the case of increased-index photonic crystal (PhC) waveguides, formed through the omission of low-dielectric media in the waveguide region. We employ the finite-difference time-domain numerical method for characterizing the beaming effect and determining the mechanisms of loss and the overall efficiency of the directional emission. We find that, while th...

In this paper, a finite difference time domain (FDTD) method is applied to investigate capabilities of an ultrawide band (UWB) radar system to detect and locate a breast tumor. The first part of these investigations concerns a phantom formed by a circular cylindrical plastic container with liquid and a small highly reflecting target. In the second part, a three-dimensional numerical breast mode...

Light-matter interaction provides a powerful means to control mechanical excitation in the nanoscale. The efficiency of this interaction reaches maximum at optical resonance. By understanding and designing the electromagnetic resonance of nanostructures, we can manipulate the electromagnetic field distribution as desired, with the benefits of enhancing the field strength and squeezing the field...

In this paper, a new dual-frequency, compact antenna, which uses an H-shaped microstrip patch with a shorting pin, is described. Compared with the conventional rectangular patch antenna, this antenna can achieve both a significant reduction of antenna size and a dual-frequency operation with a single feed. More freedoms for tuning the resonant frequencies, the frequency ratio, and the input imp...

In this paper, we have proposed an optical sensor design for urine analysis for diabetic applications. The sensor design consists of two dimensional photonic crystal ring resonator structure. Finite Difference Time Domain (FDTD) method has been used for the analysis. MEEP (MIT Electromagnetic Equation Propagation) simulation tool has been used for modeling and designing of photonic crystal ring...

The application of the Finite Difference Time Domain technique, equipped with periodic boundary conditions, can lead to the fast full-wave characterization of negative refractive index (NRI) structures. Employing the so-called sine-cosine method, the guiding and radiating properties of the NRI transmission-line medium are determined. Surface wave effects are captured, while the operation of the...

Sound localization tests were carried out with two subjects using a Virtual Auditory Display (VAD) to determine the intersubject effects on localization accuracy, of employing either acoustically measured or Finite Difference Time Domain (FDTD)-simulated Head Related Transfer Functions (HRTFs). Results indicate that the simulated HRTFs were able to yield comparable localization performance and ...

We present a bistable photonic crystal configuration consisting of a waveguide sided coupled to a single-mode cavity with instantaneous Kerr nonlinearity. We show that such a configuration can generate extremely high contrast between the bistable states in its transmission with low input power. We also provide an analytic theory that can completely account for the entire transient switching dyn...

In this paper, the authors present a new and robust conformal Finite Difference Time Domain (FDTD) algorithm for the accurate modeling of perfectly conducting objects with curved surfaces and edges. We illustrate the application of this approach by analyzing a number of representative antenna and cavity problems. These include a quarter wave monopole mounted on a perfectly conducting elliptic d...