TY - JOUR
T1 - Ionization of a P-doped Si(111) nanofilm using two-dimensional periodic boundary conditions
AU - CHAN, Anthony T L
AU - Lee, Alex J.
AU - Chelikowsky, James R.
N1 - Publisher Copyright:
© 2015 American Physical Society.
Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2015/6/25
Y1 - 2015/6/25
N2 - We examine the ionization of a P dopant in a Si(111) nanofilm using first-principles electronic structure calculations with 2D periodic boundary conditions. The electrostatic divergence of a charged periodic system is resolved by defining an electrostatic reference potential along the confined direction. After ionization, there is an overall electrostatic potential drop of the system. A nanofilm with larger periodicity can reduce the potential drop by screening the P ion, and leads to a smaller ionization energy. We compare the ionization energy calculated for the P-doped Si nanofilm with a P-doped Si nanocrystal and a P-doped Si(110) nanowire. As dimensionality decreases, quantum confinement tends to lower the ionization energy by raising the defect level. However, lower dimensionality also reduces screening after P ionization. This leads to a larger electrostatic potential drop and offsets the effect of quantum confinement on the ionization energy.
AB - We examine the ionization of a P dopant in a Si(111) nanofilm using first-principles electronic structure calculations with 2D periodic boundary conditions. The electrostatic divergence of a charged periodic system is resolved by defining an electrostatic reference potential along the confined direction. After ionization, there is an overall electrostatic potential drop of the system. A nanofilm with larger periodicity can reduce the potential drop by screening the P ion, and leads to a smaller ionization energy. We compare the ionization energy calculated for the P-doped Si nanofilm with a P-doped Si nanocrystal and a P-doped Si(110) nanowire. As dimensionality decreases, quantum confinement tends to lower the ionization energy by raising the defect level. However, lower dimensionality also reduces screening after P ionization. This leads to a larger electrostatic potential drop and offsets the effect of quantum confinement on the ionization energy.
UR - http://www.scopus.com/inward/record.url?scp=84935060495&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.91.235445
DO - 10.1103/PhysRevB.91.235445
M3 - Article
AN - SCOPUS:84935060495
VL - 91
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 1098-0121
IS - 23
M1 - 235445
ER -