arXiv subjects

S. O. Kasap

Publications and source records attributed to S. O. Kasap.

2 recordsLinked to original sources

arXiv2009

Identifying structural order in Selenium with Near-Edge Spectroscopy

We investigate the crystallization of amorphous arsenic-selenium alloys with 0%, 0.5%, 2%, 6%, 10%, and 19% arsenic by atomic concentration using synchrotron X-ray absorption spectroscopy. We identify crystalline order using the extended X-ray absorption fine structure (EXAFS) spectra and correlate this order to changes in features of the X-ray absorption near edge structure (XANES) spectra. We find supporting evidence that the structure of amorphous selenium is composed of disordered helical chains, and is therefore closer to the trigonal crystalline phase than the monoclinic crystalline phase.

cond-mat.mtrl-sci↗

arXiv2003

The Pedagogy of the p-n Junction: Diffusion or Drift?

The majority of current textbooks on device physics at the undergraduate level derive the diode equation based on the diffusion of injected minority carriers. Generally the drift of the majority carriers, or the extent of drift, is not discussed and the importance of drift in the presence of a field in the neutral regions is almost totally ignored. The assumptions of zero field in the neutral regions and conduction by minority carrier diffusion lead to a number of pedagogical problems and paradoxes for the student. The purpose of this paper is to address the pedagogical problems and paradoxes apparent in the current treatment of conduction in the pn junction as it appears in the majority of texts.

physics.ed-ph↗