### Abstract

We apply first principles density functional computational methods to study the structures, densities of states (DOS), and higher occupied molecular orbital (HOMO) - lowest unoccupied molecular orbital (LUMO) gaps of selected free-standing Ge semiconductor quantum dots up to 1.8nm. Our calculations are performed using numerical atomic orbital approach where linear combination of atomic orbital was applied. The surfaces of the quantum dots was passivized by hydrogen atoms. We find that surface passivation does affect the electronic properties associated with the changes of surface state, electron localization, and the energy gaps of germanium nanocrystals as well as the confinement of electrons inside the quantum dots (QDs). Our study shows that the energy gaps of germanium quantum dots decreases with the increasing dot diameter. The size-dependent variations of the computed HOMO-LUMO gaps in our quantum dots model were found to be consistent with the effects of quantum confinement reported in others theoretical and experimental calculation.

Original language | English |
---|---|

Title of host publication | National Physics Conference 2014, PERFIK 2014 |

Publisher | American Institute of Physics Inc. |

Volume | 1657 |

ISBN (Electronic) | 9780735412996 |

DOIs | |

Publication status | Published - 24 Apr 2015 |

Event | National Physics Conference 2014, PERFIK 2014 - Kuala Lumpur, Malaysia Duration: 18 Nov 2014 → 19 Nov 2014 |

### Other

Other | National Physics Conference 2014, PERFIK 2014 |
---|---|

Country | Malaysia |

City | Kuala Lumpur |

Period | 18/11/14 → 19/11/14 |

### Fingerprint

### Keywords

- Density Functional Theory
- Density of states
- Energy gap
- Germanium
- Quantum Dots

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*National Physics Conference 2014, PERFIK 2014*(Vol. 1657). [110006] American Institute of Physics Inc.. https://doi.org/10.1063/1.4915225

**Density functional calculation of the structural and electronic properties of germanium quantum dots.** / Anas, M. M.; Gopir, Geri Kibe.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*National Physics Conference 2014, PERFIK 2014.*vol. 1657, 110006, American Institute of Physics Inc., National Physics Conference 2014, PERFIK 2014, Kuala Lumpur, Malaysia, 18/11/14. https://doi.org/10.1063/1.4915225

}

TY - GEN

T1 - Density functional calculation of the structural and electronic properties of germanium quantum dots

AU - Anas, M. M.

AU - Gopir, Geri Kibe

PY - 2015/4/24

Y1 - 2015/4/24

N2 - We apply first principles density functional computational methods to study the structures, densities of states (DOS), and higher occupied molecular orbital (HOMO) - lowest unoccupied molecular orbital (LUMO) gaps of selected free-standing Ge semiconductor quantum dots up to 1.8nm. Our calculations are performed using numerical atomic orbital approach where linear combination of atomic orbital was applied. The surfaces of the quantum dots was passivized by hydrogen atoms. We find that surface passivation does affect the electronic properties associated with the changes of surface state, electron localization, and the energy gaps of germanium nanocrystals as well as the confinement of electrons inside the quantum dots (QDs). Our study shows that the energy gaps of germanium quantum dots decreases with the increasing dot diameter. The size-dependent variations of the computed HOMO-LUMO gaps in our quantum dots model were found to be consistent with the effects of quantum confinement reported in others theoretical and experimental calculation.

AB - We apply first principles density functional computational methods to study the structures, densities of states (DOS), and higher occupied molecular orbital (HOMO) - lowest unoccupied molecular orbital (LUMO) gaps of selected free-standing Ge semiconductor quantum dots up to 1.8nm. Our calculations are performed using numerical atomic orbital approach where linear combination of atomic orbital was applied. The surfaces of the quantum dots was passivized by hydrogen atoms. We find that surface passivation does affect the electronic properties associated with the changes of surface state, electron localization, and the energy gaps of germanium nanocrystals as well as the confinement of electrons inside the quantum dots (QDs). Our study shows that the energy gaps of germanium quantum dots decreases with the increasing dot diameter. The size-dependent variations of the computed HOMO-LUMO gaps in our quantum dots model were found to be consistent with the effects of quantum confinement reported in others theoretical and experimental calculation.

KW - Density Functional Theory

KW - Density of states

KW - Energy gap

KW - Germanium

KW - Quantum Dots

UR - http://www.scopus.com/inward/record.url?scp=84988221116&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84988221116&partnerID=8YFLogxK

U2 - 10.1063/1.4915225

DO - 10.1063/1.4915225

M3 - Conference contribution

AN - SCOPUS:84988221116

VL - 1657

BT - National Physics Conference 2014, PERFIK 2014

PB - American Institute of Physics Inc.

ER -