Theoretical investigation of defects in photonic crystals in the presence of dielectric losses (original) (raw)

Reflection properties and defect formation in photonic crystals

Applied Physics Letters, 1996

We have investigated the surface reflection properties of a layer-by-layer photonic crystal. By using a Fabry-Perot resonant cavity analogy along with the reflection-phase information of the photonic crystal, we predicted defect frequencies of planar defect structures. Our predictions were in good agreement with the measured defect frequencies. Our simple model can also predict and explain double defect formation within the photonic band gap.

Transmission Properties of 1D Defect Metallic-Dielectric Photonic Crystals

2016

In this study, we have theoretically investigated transmission properties of transverse electric fields at visible region frequencies in one dimensional defect Metallic-Dielectric photonic crystals. We examined the effect of photonic crystals thickness, layer numbers, layer refractive indexes and defects on transparency. We use OptiFDTD software for simulations. OptiFDTD software uses finite-different time-domain method.

Defect-mode-like transmission and localization of light in photonic crystals without defects

2010

It is shown that far-and near-field effects, which are similar to those arising in transmission through finite-thickness photonic crystals ͑PCs͒ with structural defects, can be obtained in the conventional defect-free dielectric square-lattice PCs. Multiple narrow peaks of total transmission can appear within a frequency range, where the noncircular isofrequency dispersion contours of one type are quickly transformed for a higher-order Floquet-Bloch wave to the noncircular contours of the other type, leading to a frequency-domain passband being very narrow within a certain range of variation of the angles of incidence. In this regime, the mirror reflectance of the equivalent Fabry-Pérot resonator takes rather large values, which correspond to large values of Q factor and group index of refraction, strong field localization, and good isolation of the transmission peaks from each other. In some examples presented, Q factor exceeds 10 4 .

Properties of the defect modes in 1D lossy photonic crystals containing two types of negative-index-material defects

Journal of Electromagnetic Waves and Applications, 2013

In this paper, the characteristic matrix method is employed to theoretically investigate the propagation of electromagnetic waves through one-dimensional defective lossy photonic crystals (PCs) composed of negative index materials (NIMs) and positive index materials (PIMs). We consider symmetric and asymmetric geometric structures with two different types of NIM defect layers at the center of the structure. The effects of the polarization and the angle of incidence on the defect modes in the transmission spectra of both structures are investigated. The results show that the number of the defect modes within the photonic band gap (PBG) depends on the type of the NIM defect layer and is independent of the geometrical structure.

Characterization of defect modes in one-dimensional photonic crystals: An analytic approach

Physica B: Condensed Matter, 2009

We introduce an analytical model to investigate the localized defect modes associated with a defect cell inserted in a one-dimensional photonic crystal for both transverse electric (TE) and transverse magnetic (TM) polarizations, at an arbitrary angle of incidence. The defect cell, which is made of two dielectric constituents, leads to the appearance of several localized defect modes within the photonic band gaps. We develop an analytical approach based on the both transfer matrix and Green's function methods to determine the number and frequency of the defect modes that can be controlled easily by varying the parameter values of the constituent layers of the photonic crystal. The method demonstrates that the electric field amplitude depends on the defect cell position in the photonic crystal while the defect mode frequency is independent of it. This method is useful for photonic band gap engineering and designing the photonic-based devices.

Defect modes of a two-dimensional photonic crystal in an optically thin dielectric slab

Journal of the Optical Society of America B, 1999

We present a three-dimensional finite-difference time-domain analysis of localized defect modes in an optically thin dielectric slab that is patterned with a two-dimensional array of air holes. The symmetry, quality factor, and radiation pattern of the defect modes and their dependence on the slab thickness are investigated.

Accurate model of electromagnetic wave propagation in unidimensional photonic crystals with defects

Journal of …, 2007

Complete vectorial studies of electromagnetic wave propagation in complex media are difficult and computationally intensive. A mathematical continuous model can simplify some of such difficulties. Using this technique, we have modeled the propagation of electromagnetic plane waves through a semiinfinite photonic crystal with defects. The model is exact in the sense that the only approximations are the numerical accurate solution of ordinary differential equations and the simulation of defects by a high frequency sinusoidal continuous variation of the main crystal period.

Transmission through photonic crystals with multiple line defects at oblique incidence

Journal of the Optical Society of America B Optical Physics, 2008

Transmission through two-dimensional photonic crystals (PhCs) with several (non)periodic line defects, each being created by removing a single row of rods, are studied with the emphasis put on angular selectivity. Most of the observed features appear due to a hybrid mechanism, which is realized as a common effect of the splitting of a transmission peak being the result of peculiar coupling of individual defect-mode resonators, and the angle-dependent guided-wave cavity effect, which depends on the chosen dispersion. In the case of zero-order propagation, the role of periodic location of line defects is demonstrated. A rich variety of effects can be obtained in the angle domain within a rather narrow frequency range, which contains eigenfrequencies of defect modes. Peculiarities of the transmission peaks arising in the case of first-order propagation are considered in both angle and frequency domains. It is shown that the defect-mode related peaks can be close by to the peaks, which appear due to resonances within the pieces of PhC separated by line defects and their coupling. For the effects observed while two beams are propagating, the presence of multiple defects is rather critical than the periodicity of their location.

Electrical modeling of photonic crystal defects

Microwave and Optical Technology Letters, 2012

A transmission line model of a planar photonic crystal (PC) waveguide is presented here. Electrical characteristics of single and multiple point defects in a PC waveguide are investigated. It is shown that a point defect in the waveguide can be modeled as a reactance connected across the transmission line. Investigation shows that depending on the size and refractive index, a point defect can be inductive or capacitive and its reactance can vary over a wide range. A double defect behaves as a bandpass filter. V