Two dimensional microwave band gap structures have been constructed using lossy cylindrical glass samples (ε' = 5.5 and ε" = 0.1). The power transmission spectra observed between 10 and 20 GHz for both square and triangular structures with three different lattice spacing (2.5, 1.4 and 0.9 cm) are explained in terms of the lattice spacing, filling fraction and loss tangent. The experimental results and the theoretical values agree well for the structures having higher filling fraction. Also, the values predicted from the scaling procedure agree well with the experimental values. The appearance of acceptor modes due to the introduction of defects in these structures is also reported.

Venkatachalam Subramanian

Department Of Physics

E. D V Nagesh

Vemuri Rama Krishna Murthy

Dielectric materials

Mathematical models

MICROWAVES

Permittivity

Power transmission

Radio waves

Refractive index

Vectors

GLASS RODS

microwave propagation

PHOTONIC BAND GAP (PBG)

Photonic crystals

Wave propagation

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

European Physical Journal B

Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are formed by removing the substrate material in a periodic manner. This paper also demonstrates that these structures can serve as a non-destructive characterization tool for materials, a duplexor and frequency selective coupler. The paper presents both experimental results and theoretical simulation based on a commercially available finite element methodology for comparison. © Indian Academy of Sciences.

Pramana - Journal of Physics

Microstrip microwave band gap structures

We report the theoretical work on the photonic band gap structures suitable for microwave frequency region formed by magnetic materials (ε = 9.87 and μ = 2.17) using plane wave expansion method. The structures under analysis are two-dimensional square and triangular lattices. The calculated band gap between 10 and 20 GHz region is anlaysed for the effect due to lattice spacing and the property of the material. The results are also compared with that of pure dielectric case. Obtained results indicate that both impedance and effective refractive index are responsible for the gap width and mid-gap frequency. © 2006 Elsevier B.V. All rights reserved.

Physica B: Condensed Matter

Numerical study of the effect of permeability on square and triangular microwave band gap structures

Photonic Crystals

Journal of Applied Physics

Defect modes in coaxial photonic crystals

Applied Physics Letters

Experimental demonstration of photonic crystal based waveguides

IEEE Transactions on Microwave Theory and Techniques

Two-dimensional photonic crystal Fabry-Perot resonators with lossy dielectrics

Defect structures in metallic photonic crystals

Microwave propagation in two dimensional structures using lossy cylindrical glass rods

Journal	European Physical Journal B
ISSN	14346028
Open Access	No