Mr. Muhammad Tahir, Lecturer, Department of Physics, Abdul Wali Khan University Mardan has successfully defended his PhD thesis in the area of "Organic Semiconductor Physics" on Wednesday, May 28, 2014 at Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, KPK, Pakistan. His thesis was supervised by Prof. Dr. Muhammad Hassan Sayyad. Besides the committee members, including Dean Faculty of Engineering Sciences and two external examiners, it was an open session and a large number of MS and PhD students participated in this presentation. After an hour presentation followed by viva with the external and internal examiners, his thesis was approved by the committee members for the award of PhD degree. He had done a part of his research work during his six months visit as a research fellow at Cavendish Lab, University of Cambridge UK. Mr. Tahir has published 08 papers in international journals of impact factors.