Abstract
We apply a stochastic version of an optimally tuned range-separated hybrid functional to provide insight on the electronic properties of P- and B-doped Si nanocrystals of experimentally relevant sizes. We show that we can use the range-separation parameter for undoped systems to calculate accurate results for dopant activation energies. We apply this strategy for tuning functionals to study doped nanocrystals up to 2.5 nm in diameter at the hybrid functional level. In this confinement regime, the P and B dopants have large activation energies and have strongly localized states that lie deep within the energy gaps. Structural relaxation plays a greater role for B-substituted dopants and contributes to the increase in activation energy when the B dopant is near the nanocrystal surface.
| Original language | American English |
|---|---|
| Article number | 035112 |
| Journal | Physical Review B |
| Volume | 102 |
| Issue number | 3 |
| DOIs | |
| State | Published - 15 Jul 2020 |
Bibliographical note
Funding Information:The authors thank Helen Eisenberg for valuable discussions and coding assistance. We acknowledge support from the Center for Computational Study of Excited State Phenomena in Energy Materials (C2SEPEM) at the Lawrence Berkeley National Laboratory, which is funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under Contract No. DE-AC02-05CH11231 as part of the Computational Materials Sciences Program. Computational resources were provided by the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231. We would also like to thank the computational resources provided by XSEDE under Project No. TG-CHE170058. R.B. gratefully thanks the Israel-U.S. Binational Science Foundation (BSF) Grant No. 2018368.
Publisher Copyright:
© 2020 American Physical Society.