**Meet the editor**

Dr. Alireza Bananej received his B.Sc degree in applied physics in 1989. Then he joined Laser Research Center of NSTRI and worked in the field of optical coating technology. In 1996 he received his M.Sc degree from Amirkabir University of Technology in applied physics. In 2000 he joined the physics department, nonlinear photonics lab of Harbin Institute of Technology (HIT) in China and

worked in the field of low power and controllable all optical switching. He received his Ph.D degree from HIT in 2004 and returned to Laser Research Center of NSTRI. Since 2004 he has been studying fiber laser, high power and fast optical coating and application of photonic crystals.

## Contents

#### **Preface XI**


Alessandro Settimi

## Preface

As a reason of information explosion, electronic communication networks are not sufficient for high bit rate data transmission. This problem has been solved by optical networks which caused the birth of a new area of technology, photonics. In photonic circuits photons play the dominant role and they transfer the optical data. With the growth of the photonics tech‐ nology, a new area started to grow as photonic crystals which now play an important role in designing and manufacturing compact photonic devices.

Photonic crystals are structures with alternative dielectric constant in one, two or three di‐ mensions which are called one, two or three dimensional photonic crystals. As a reason of alternative dielectric constant, by solving Maxwell's equations photonic band gap can ap‐ pear. By using the properties of photonic band gap, many interesting phenomena such as slow light generation, dispersion engineering in a compact and low size device can be ach‐ ieved.

> **Alireza Bananej** Laser and Optics Research School, NSTRI, IRAN

#### **Chapter 1**
