Acknowledgements

All the praise is due to Allah (God) the lord of heavens and the earth, who enabled me to carry out this difficult task and made this year a memorable year for me.

Special thanks to my supervisor, Dr. John Atkinson, whose invaluable support, guidance and supervision helped me all the way through. I sincerely appreciate his kindness and welcoming attitude. His comments and corrections helped tremendously in improving my work.

Gratitude is also due to Mr. Sheraz Ali, who provided invaluable support in setting up of equipment, and development of programming software. Without his help, it would have been impossible to complete this work in time. Special thanks to all the technical staff for their cooperation. Particularly, the technicians Peter and Ross of forming laboratory in Pariser building deserve extra appreciation.

This section will remain incomplete without expressing thanks to all my friends especially Awais, Farhan and Kamran whose friendship made this year a memorable year for me.

Thanks are due to Alisha, who was like a family member to me. I will long remember her kindness and courage. Without her Manchester would have been a lonely place. May Allah bless her in every thing.

Thanks are due to my sweet brother Usman, May God always keep him happy.

Lastly but not the least importantly, appreciation is due to my fiancé Sumaira for having faith in me and cheering me all the way through. And giving me fresh hope each new day. May Allah always bless her                                                        Thank you all.