Understanding Electron Transport Through Phosphorus Atoms Embedded in Silicon*

Shriya Haravu 1, Maicol A. Ochoa 2

1Department of Physics, University of North Carolina at Chapel Hill, USA

 2 Institute for Research in Electronics and Applied Physics, University of Maryland College Park, USA

Electron transport through atoms can be described with Landauer theory which accounts for the quantum nature of the electron’s movement, assumes momentum is conserved within the atom, and incorporates Coulomb repulsion in a unique way. We model differential conductance through one and two phosphorus atoms embedded in silicon as a function of several parameters governing which atomic energy levels are open for transport, and discuss the validity of the Landauer model in representing electronic properties of these systems. Moreover, we observe how the differential conductance varies as a function of driving potentials and variables relating to the electronic structure of the P atoms, the silicon matrix, and the connections between them, thus realizing how each of these parameters affects transport and control. Control at this scale has applications in shrinking transistors, quantum computing, and semiconductor materials. Finally, in trying to reproduce experimental figures for single, double, and multiple impurities, we find the strengths and restrictions of the model.